About ten days ago I suddenly started having a problem with my PC
rebooting, started from nothing to doing it very regularly, no gradual
development into the problem. Sometimes it reboots very quickly,
sometimes it will run for an hour or so without any problem. I ran my
virus and malware scans, nothing new there, and have blown out the box
for dust buildup, checked power connections, memory seating, etc. Don't
think it's windows or a hard drive problem, since it sometimes reboots
before even getting to the load point. I have a hardware monitor
function in the BIOS, and have watched readings there until it reboots,
and not much indication of a problem - voltages look okay, CPU temp
doesn't get alarmingly high. I was away for a week, came home and the
problem started up with a vengeance, couldn't even get Windows loaded,
now has backed off a little.
My box has an MSI K8N Neo Platinum mobo, Athlon64 3400+ proc, 1 gig
Corsair performance memory, ATI 800XT AIW, Enermax 420W PS, XP SP2.
Only recent hardware change was swapping out the optical drive and
adding a new SATA hard drive a number of weeks ago (now have three, the
others EIDE); everything worked well for quite a while after. The rest
is about two years old, last rebuild. I did move some cabling around
while doing the changes, and I noticed that one cable might have been
contacting the CPU fan a bit, although not stopping it or causing a lot
of noise. There were some occasional odd noises just before the reboot
problem started, and I was a bit concerned about a hard drive going
south at that point, but may have been the fan. Nothing lately, though.
I assume first it's a heat problem, but the box is big and cool and all
fans working. I've been a little concerned about the CPU fan, so
thinking of replacing that (retail cooler); I'm not sure if it's always
spinning up faster as the temperature rises. It doesn't seem to get very
hot, usually first readings are around 47 degrees C, work up over 50,
the fan spins up faster around 55 and pushes it down a few degrees, and
sometimes the reading just before a reboot is just 50 or a bit more. Not
sure how accurate or delayed those readings are, though. Next thought is
the PS, but no unusual readings there, with the same caveats on those.
Any ideas on what's happening and fixes? I haven't done that much yet,
but this is a new one for me and has me a bit stumped. Thanks in advance
for any assistance.
On Fri, 09 Mar 2007 12:00:43 -0800, Mark N
<menusbaum@NYETSPAMearthlink.net> wrote:
>About ten days ago I suddenly started having a problem with my PC
>rebooting, started from nothing to doing it very regularly, no gradual
>development into the problem. Sometimes it reboots very quickly,
>sometimes it will run for an hour or so without any problem. I ran my
>virus and malware scans, nothing new there, and have blown out the box
>for dust buildup, checked power connections, memory seating, etc. Don't
>think it's windows or a hard drive problem, since it sometimes reboots
>before even getting to the load point.
What are you calling the "load point", what exact spot in
the boot process? Nevermind if what you wrote below means
that it doesn't even have to have gone beyond the bios menu,
leaving it sitting at that health page is a good place to
isolate hardware from software.
>I have a hardware monitor
>function in the BIOS, and have watched readings there until it reboots,
>and not much indication of a problem - voltages look okay, CPU temp
>doesn't get alarmingly high. I was away for a week, came home and the
>problem started up with a vengeance, couldn't even get Windows loaded,
>now has backed off a little.
Oh, disregard the above question, since it seems you can
leave the system sitting in the bios health menu and have it
happen.
Most likely suspects are a dodgy power supply or motherboard
failing. You might inspect the capacitors on the
motherboard, even in the PSU after leaving it unplugged from
AC for a few minutes.
>My box has an MSI K8N Neo Platinum mobo, Athlon64 3400+ proc, 1 gig
>Corsair performance memory, ATI 800XT AIW, Enermax 420W PS, XP SP2.
>Only recent hardware change was swapping out the optical drive and
>adding a new SATA hard drive a number of weeks ago (now have three, the
>others EIDE); everything worked well for quite a while after. The rest
>is about two years old, last rebuild. I did move some cabling around
>while doing the changes, and I noticed that one cable might have been
>contacting the CPU fan a bit, although not stopping it or causing a lot
>of noise. There were some occasional odd noises just before the reboot
>problem started, and I was a bit concerned about a hard drive going
>south at that point, but may have been the fan. Nothing lately, though.
Reinspect that cable to be sure it isn't shorting out on
anything. Inspect the other cards & cables while the system
is open. If nothing else helps, reduce system to a minimal
state by disconnecting all parts unessential towards getting
a POST and the bios menu scenario in which it is resetting.
>
>I assume first it's a heat problem, but the box is big and cool and all
>fans working. I've been a little concerned about the CPU fan, so
>thinking of replacing that (retail cooler); I'm not sure if it's always
>spinning up faster as the temperature rises. It doesn't seem to get very
>hot, usually first readings are around 47 degrees C, work up over 50,
>the fan spins up faster around 55 and pushes it down a few degrees, and
>sometimes the reading just before a reboot is just 50 or a bit more. Not
>sure how accurate or delayed those readings are, though. Next thought is
>the PS, but no unusual readings there, with the same caveats on those.
If the temp never gets above 55 it's cool enough (save for
some extreme overclock), assuming the temp report is
accurate. If it's getting much hotter you should be able to
fairly easily feel the heatsink as hot rather than mildly
warm. I'm assuming the chipset and other parts are
seemingly cool enough as well.
An intermittent failure related to temp could instead be a
crack in a circuit board (motherboard most likely) or a cold
solder joint. In these modern times of RoHS, lead-free
solder, it could even be tin whiskers that intermittently
short as thermal expansion closes the gap between two
component leads. Is it possible the case has a standoff
where there shouldn't be one, shorting against the back of
the motherboard once it has expanding slightly from temp
change? One thing to try would be taking the parts out of
the case, laying them out on a non-conductive (not
anti-static) surface for another trial.
A PSU can fail such that voltages look ok until the event,
if you have a spare you might try it (all else failing) or
order one from someplace with a good return policy.
>
>Any ideas on what's happening and fixes? I haven't done that much yet,
>but this is a new one for me and has me a bit stumped. Thanks in advance
>for any assistance.
Some ATI X800 video cards seem prone to fail after awhile,
if you had another card you might swap that in temporarily
but playing odds it seems less likely.
On 2007-03-09, Mark N <menusbaum@NYETSPAMearthlink.net> wrote:
> About ten days ago I suddenly started having a problem with my PC
> rebooting, started from nothing to doing it very regularly, no gradual
> development into the problem. Sometimes it reboots very quickly,
> sometimes it will run for an hour or so without any problem. I ran my
> virus and malware scans, nothing new there, and have blown out the box
> for dust buildup, checked power connections, memory seating, etc. Don't
> think it's windows or a hard drive problem, since it sometimes reboots
> before even getting to the load point. I have a hardware monitor
> function in the BIOS, and have watched readings there until it reboots,
> and not much indication of a problem - voltages look okay, CPU temp
> doesn't get alarmingly high. I was away for a week, came home and the
> problem started up with a vengeance, couldn't even get Windows loaded,
> now has backed off a little.
Kony has already mentioned the PSU and possible bad electrolytics
- they're both possibilities but it would be an unusual failure
mode since if you're still in the BIOS your machine will be at
nowhere near full load. I'd be thinking about issues with the
quality of the mains too and be tempted to try running it through
a surge protector or ideally a UPS.
Has anything happened to the mains supply that you are aware of?
Any major construction work locally, electrical storms or gales/floods
that may have caused damge?
On Fri, 9 Mar 2007 22:18:08 +0000 (UTC), Andrew Smallshaw
<andrews@sdf.lonestar.org> wrote:
>On 2007-03-09, Mark N <menusbaum@NYETSPAMearthlink.net> wrote:
>> About ten days ago I suddenly started having a problem with my PC
>> rebooting, started from nothing to doing it very regularly, no gradual
>> development into the problem. Sometimes it reboots very quickly,
>> sometimes it will run for an hour or so without any problem. I ran my
>> virus and malware scans, nothing new there, and have blown out the box
>> for dust buildup, checked power connections, memory seating, etc. Don't
>> think it's windows or a hard drive problem, since it sometimes reboots
>> before even getting to the load point. I have a hardware monitor
>> function in the BIOS, and have watched readings there until it reboots,
>> and not much indication of a problem - voltages look okay, CPU temp
>> doesn't get alarmingly high. I was away for a week, came home and the
>> problem started up with a vengeance, couldn't even get Windows loaded,
>> now has backed off a little.
>
>Kony has already mentioned the PSU and possible bad electrolytics
>- they're both possibilities but it would be an unusual failure
>mode since if you're still in the BIOS your machine will be at
>nowhere near full load.
That is true, but there are a couple factors that offset
this.
1) WIthout a modern OS loaded, there is not
ACPI/HLT-Cooling, the CPU is nearet to full load than it is
to the idle (windows) power consumption level. When
everything is cooler still the components, particularly
power electronics, have different parameters that change
along with temp. Normally these are negligable in a proper
design, BUT if a part is failing progressively, there will
be a certain scenario in which this degraded performance
first surfaces... IF it degrades slow enough to notice it.
Temperature increase can make a functional but defective computer
apparent. High reliability equipment gets thermal cycled - sometimes
called 'burn in' testing - to find defects before failure occurs. Is
your heatsink incorrect? Well then the computer never did what it
must do - work inside a room at 100 degrees F and be perfectly happy.
Your heatsink, if selected or installed by one with engineering
knowledge such as the manufacturer, is not a problem. However if
selected by just any computer assembler, then start asking questions
that were answered by that heatsink manufacturer. What is its degree
C per watt number? Don't just assume and then start replacing
things. That is called shotgunning.
Your computer is intermittent. Therefore use a hairdryer on high to
heat selective parts at temperatures uncomfortable to touch. That is
a perfectly normal temperature to all working retail electronics.
This is also when comprehensive hardware diagnostics best find
failures. At higher temperature, defective electronics then will fail
consistently. Just another way to find defects and how to have found
that defect long before your problems were apparent.
Hardware monitor will show changes (a monitor) but is not valid as a
voltage measurement until calibrated - which is why you need a 3.5
digit multimeter. A tool so 'complex' as to be sold even in K-mart.
Any voltage below 3.23, 4.87, or 11.7 is a problem and would explain
intermittent crashes.
Line voltages should have no effect on a computer. This assumes the
power supply was purchased with internal functions that were even
standard 30 years ago. AC electric voltages must drop so low that
incandescent lamps are at less than 40% intensity and still computer
both starts and runs 100% OK. Are your lights dimming that low? If
not, then AC voltage is not (should not be) a problem. Anything that
a power conditioner or UPS would do to solve a problem is supposed to
be already inside the power supply. Some power supplies installed by
those who do not learn electricity are so inferior as to need power
conditioning. Fix the problem. Don't purchase something many times
more money to only cure symptoms. Don't cure symptoms. Eliminate the
problem.
As noted earlier, room temperature and therefore CPU temperatures
must increase 30 degree F higher; CPU temperature still below
manufacturer max spec numbers. Again, consult numbers such as
manufacturer specs. Confirm voltages per limits provided above.
Eliminate potential suspects completely and then move on to other
suspects. Hair dryer, multimeter, manufacturer specs ... just some
simple things that answer questions with yes or no. Answers with
'maybe' are wasted time; often from speculation such as AC line noise
solved by a surge protector or UPS.
Each useful solution is not only recommended. Reasons why it is
useful is also important. No reasons why? This is why some recommend
surge protectors or UPS as a solution.
Meanwhile, if I understand this correctly, your problem even occurs
when only in BIOS. Now we have limited the problem to very few
suspects. Only a few parts of a motherboard, a tiny part of memory,
the video controller (maybe), and a power supply 'system'.
On Mar 9, 3:00 pm, Mark N <menusb...@NYETSPAMearthlink.net> wrote:
> About ten days ago I suddenly started having a problem with my PC
> rebooting, started from nothing to doing it very regularly, no gradual
> development into the problem. Sometimes it reboots very quickly,
> sometimes it will run for an hour or so without any problem. I ran my
> virus and malware scans, nothing new there, and have blown out the box
> for dust buildup, checked power connections, memory seating, etc. Don't
> think it's windows or a hard drive problem, since it sometimes reboots
> before even getting to the load point. I have a hardware monitor
> function in the BIOS, and have watched readings there until it reboots,
> and not much indication of a problem - voltages look okay, CPU temp
> doesn't get alarmingly high. I was away for a week, came home and the
> problem started up with a vengeance, couldn't even get Windows loaded,
> now has backed off a little.
>
> My box has an MSI K8N Neo Platinum mobo, Athlon64 3400+ proc, 1 gig
> Corsair performance memory, ATI 800XT AIW, Enermax 420W PS, XP SP2.
> Only recent hardware change was swapping out the optical drive and
> adding a new SATA hard drive a number of weeks ago (now have three, the
> others EIDE); everything worked well for quite a while after. The rest
> is about two years old, last rebuild. I did move some cabling around
> while doing the changes, and I noticed that one cable might have been
> contacting the CPU fan a bit, although not stopping it or causing a lot
> of noise. There were some occasional odd noises just before the reboot
> problem started, and I was a bit concerned about a hard drive going
> south at that point, but may have been the fan. Nothing lately, though.
>
> I assume first it's a heat problem, but the box is big and cool and all
> fans working. I've been a little concerned about the CPU fan, so
> thinking of replacing that (retail cooler); I'm not sure if it's always
> spinning up faster as the temperature rises. It doesn't seem to get very
> hot, usually first readings are around 47 degrees C, work up over 50,
> the fan spins up faster around 55 and pushes it down a few degrees, and
> sometimes the reading just before a reboot is just 50 or a bit more. Not
> sure how accurate or delayed those readings are, though. Next thought is
> the PS, but no unusual readings there, with the same caveats on those.
>
> Any ideas on what's happening and fixes? I haven't done that much yet,
> but this is a new one for me and has me a bit stumped. Thanks in advance
> for any assistance.
[Comments regarding overheating snipped from here but will be
referred back to later]
> Line voltages should have no effect on a computer. This assumes the
> power supply was purchased with internal functions that were even
> standard 30 years ago. AC electric voltages must drop so low that
> incandescent lamps are at less than 40% intensity and still computer
> both starts and runs 100% OK. Are your lights dimming that low? If
Yes, this amount of drop could be perfectly reasonable. Even if
we accept your figures (which sound arbitrary to me, as did your
minimum voltages) a 60% dip in illumination is an unexceptional
sag. Recall that the human eye is logarithmic in behaviour - a
60% drop at normal levels of indoor illumination would be _perceived_
as a drop in the region of 10%. When you consider that it ceases
to be impossible and more a reasonably common occurance.
I do accept in part your comments about the filtering capability
of switched mode power supplies, they do have a certain amount of
resilience built in. But that is mainly either a function of the
way they work (as in the case of tolerance to variations in supply
voltage) or a minimum level to ensure proper operation for at least
the majority of the time (as is the case for protection against
transients). Both have their limits. A UPS or surge protector
mitigates (not so) exceptional events over and above those expected
in normal operation.
One other point: the UPS on this machine is set to switch in at
184 V against a mains rating of 230 V. I hear the relays switch
over momentarily maybe a couple of times a week. It may do it more
often and I just don't notice. More severe sags can actually last
long enough for the alarm to briefly sound - that's much rarer but
still maybe every three months on average.
> simple things that answer questions with yes or no. Answers with
> 'maybe' are wasted time; often from speculation such as AC line noise
> solved by a surge protector or UPS.
So, you can immediately identify the cause of any problem without
first running through a list of hypotheses to be considered and
eliminated?
> Each useful solution is not only recommended. Reasons why it is
> useful is also important. No reasons why? This is why some recommend
> surge protectors or UPS as a solution.
Why did I suggest the power as a _possible_ cause (unlike you I do
not claim to have a difinitive answer, I merely offered a suggestion
based on experience)? Well, we're not talking about a clear and
apparent equipment failure here, so the first question I'd ask is
"So what's changed?" This is basic troubleshooting methodology.
If we take the OP at their word then nothing has changed to the
system so the next step is to look at external factors, the mains
being one of them. If you refer back to my original post I did
ask about any factors that the poster may have known about that
could affect the local power supply, although of course the OP may
not be aware of routine maintenance or upgrade work being carried
out.
[Earlier commments]
> Temperature increase can make a functional but defective computer
> apparent. High reliability equipment gets thermal cycled - sometimes
> called 'burn in' testing - to find defects before failure occurs. Is
> your heatsink incorrect? Well then the computer never did what it
> must do - work inside a room at 100 degrees F and be perfectly happy.
> Your heatsink, if selected or installed by one with engineering
> knowledge such as the manufacturer, is not a problem. However if
> selected by just any computer assembler, then start asking questions
> that were answered by that heatsink manufacturer. What is its degree
> C per watt number? Don't just assume and then start replacing
> things. That is called shotgunning.
You asked for a justification for my suggestion regarding the mains
which I was happy to give. Now, given that the system hasn't
changed, why do you suspect it has suddenly started to suffer
through some kind of thermal stress?
>One other point: the UPS on this machine is set to switch in at
>184 V against a mains rating of 230 V. I hear the relays switch
>over momentarily maybe a couple of times a week. It may do it more
>often and I just don't notice. More severe sags can actually last
>long enough for the alarm to briefly sound - that's much rarer but
>still maybe every three months on average.
Buy an Active PFC PSU and be done with the UPS wear by
lowering the voltage setting. It should not need to come on
at 184V for the computer. Maybe something else you have
might, but any decent PSU should have no problem, it would
just lower the max possible output from the PSU but that max
is within the range of margin it should already have if
suitably sized for the system.
Nothing arbitrary was posted. Experience alone (without fundamental
facts and numbers) results in junk science reasoning - also called
speculation. That guess on illumination is just that - speculation.
A computer must work just fine even when bulb illumination drops to
below 40%. Formulas for numbers of voltage and illumination are an
industry standard - see IES Handbook. Experience alone does not
provide this.
Switching power supply 'system' makes those AC electric problems
irrelevant as even defined by another industry standard (CBEMA) of 30
years ago. Industry standard numbers demonstrate why all appliances
work just fine without UPSes or power conditioners. Computer supplies
typically are even more resilient. How many other household
appliances are failing more frequently? Some must be if AC electric is
reason for failure as Andrew speculates. More numbers from both
standards and experience - one needs both - are provided below.
Your AC voltages must maintain specific limits at different points
in household distribution. 230 volts must not drop below 205 volts.
Yes, another standard. Sometimes voltage does drop lower. Then those
with both experience and knowledge locate wiring problems. They don't
install power conditioning.
Meanwhile a 230 volts UPS may flip to battery backup mode typically
at 200 volts. (Yours trips at an untypically low 185 volts - well look
how much lower all computers must work so that your UPS can trip at
185). If Andrews' UPS is tripping daily, experience and the numbers
says Andrews should identify a marginal wiring problem - maybe a loose
screw. Since Andrew only uses experience, then Andrew considers
acceptable what is really unacceptable. Just another reason why
experience without learning fundamental technology results in
erroneous conclusions.
230 volt power supplies must work just fine with 100% load when AC
voltage is even lower - 180 VAC. This even stated in Intel ATX
standards. Does Andrew still think anything posted was arbitrary? I
don't do arbitrary.
For Mark N and the bottom line: a computer must work just fine even
when incandescent lamps dim to 40% intensity. These both from
industry standard numbers and from too many decades of experience. If
PSU voltages are too low and cause a reboot, then problem is apparent
in multimeter numbers defined previously or in http://tinyurl.com/yvf9vh .
Meter numbers will either report voltages just fine (so we move on to
other suspects as defined by Kony) or report power supply 'system' as
reason for reboot.
As Kony also notes:
> If the temp never gets above 55 it's cool enough
System also must be stable when air temperatures are raised another
30 degree F. Heat causing failure in a 70 degree room - then hardware
is obviously defective. Heat typically is a great diagnostic tool to
find defects; not something to be cured. Increased heat can make
reboots more frequent. Again heat used to identify a defect.
Obvious symptoms such as bulging capacitors may also find a
problem. But again, reason for failure is definitive - therefore a
useful tool to find defect.
Fact that reboot occurs even when only in BIOS is another useful
fact that limits problem to very few suspects as posted previously.
Some recommend UPSes or power conditioners when basic knowledge (ie
all those industry standards) is not first learned. Experience alone
often results only in speculation. If a UPS or power conditioner
'fixes' the problem, then power supply 'system' is probably defective,
or incandescent lamps are dimming excessively and obviously.
How to find reasons for reboot? Procedure also provided in http://tinyurl.com/yvf9vh
and two minutes exonerates or condemns power supply
'system' (including AC voltage problems). Also useful are what those
voltages do when system reboots. If problem is not in the power
supply 'system' (as meter will report), then move on to other
suspects. Don't just speculate which is what happens when experience
is not tempered by fundamental knowledge - ie the above numbers. Get
numbers to know what is and is not working - without speculation.
Experience without those standards and numbers creates only
speculation. I don't do arbitrary.
On Mar 10, 5:44 pm, Andrew Smallshaw <andr...@sdf.lonestar.org> wrote:
> Yes, this amount of drop could be perfectly reasonable. Even if
> we accept your figures (which sound arbitrary to me, as did your
> minimum voltages) a 60% dip in illumination is an unexceptional
> sag. Recall that the human eye is logarithmic in behaviour - a
> 60% drop at normal levels of indoor illumination would be _perceived_
> as a drop in the region of 10%. When you consider that it ceases
> to be impossible and more a reasonably common occurance.
>
> I do accept in part your comments about the filtering capability
> of switched mode power supplies, they do have a certain amount of
> resilience built in. But that is mainly either a function of the
> way they work (as in the case of tolerance to variations in supply
> voltage) or a minimum level to ensure proper operation for at least
> the majority of the time (as is the case for protection against
> transients). Both have their limits. A UPS or surge protector
> mitigates (not so) exceptional events over and above those expected
> in normal operation.
>
> One other point: the UPS on this machine is set to switch in at
> 184 V against a mains rating of 230 V. I hear the relays switch
> over momentarily maybe a couple of times a week. It may do it more
> often and I just don't notice. More severe sags can actually last
> long enough for the alarm to briefly sound - that's much rarer but
> still maybe every three months on average.
> ...
>
> So, you can immediately identify the cause of any problem without
> first running through a list of hypotheses to be considered and
> eliminated?
> ...
>
> Why did I suggest the power as a _possible_ cause (unlike you I do
> not claim to have a difinitive answer, I merely offered a suggestion
> based on experience)? Well, we're not talking about a clear and
> apparent equipment failure here, so the first question I'd ask is
> "So what's changed?" This is basic troubleshooting methodology.
>
> If we take the OP at their word then nothing has changed to the
> system so the next step is to look at external factors, the mains
> being one of them. If you refer back to my original post I did
> ask about any factors that the poster may have known about that
> could affect the local power supply, although of course the OP may
> not be aware of routine maintenance or upgrade work being carried
> out.
> ...
>
> You asked for a justification for my suggestion regarding the mains
> which I was happy to give. Now, given that the system hasn't
> changed, why do you suspect it has suddenly started to suffer
> through some kind of thermal stress?
> For Mark N and the bottom line: a computer must work just fine even
> when incandescent lamps dim to 40% intensity. These both from
> industry standard numbers and from too many decades of experience. If
> PSU voltages are too low and cause a reboot, then problem is apparent
> in multimeter numbers defined previously or in
> http://tinyurl.com/yvf9vh .
> Meter numbers will either report voltages just fine (so we move on to
> other suspects as defined by Kony) or report power supply 'system' as
> reason for reboot.
> As Kony also notes:
>> If we take the OP at their word then nothing has changed to the
>> system so the next step is to look at external factors, the mains
>> being one of them. If you refer back to my original post I did
>> ask about any factors that the poster may have known about that
>> could affect the local power supply, although of course the OP may
>> not be aware of routine maintenance or upgrade work being carried
>> out.
>> ...
>>
>> You asked for a justification for my suggestion regarding the mains
>> which I was happy to give. Now, given that the system hasn't
>> changed, why do you suspect it has suddenly started to suffer
>> through some kind of thermal stress?
Thanks to everyone for their suggestions, and the worthwhile discussion
on power issues. But I seem to have discovered the problem doing one of
the things Kony originally suggested. First, what it apparently isn't:
- No high heat readings, and while the suggestion that the readings
need to be calibrated in order to be determined correct, they are
relatively the same as they've been since I built the box two years ago.
So my guess is no heat problems.
- Not a memory voltage issue; I tried that and no change, and also
tried increasing the Vcore voltage, as the readings have always been at
1.44 instead of 1.5, but no help.
- No power issues in my home, lights never dim, and reboots have been
constant, no more or less at peak and off-peak hours.
- I also noticed that the PC was having performance problems when it
was up and running, things like video playback skipping and lagging when
they hadn't before.
The box had never before rebooted until two weeks ago, and the problem
recurs at least every hour, and sometimes every few seconds - I woke up
last night to continuous beeping, each time the PC POSTed. The last
change to the box was several weeks earlier, when I changed optical
drives and added a hard drive, so I decided to start there. I had been a
bit concerned about the SATA HD, as I seem to recall that early SATA
mobos have had some problems, so I unhooked it and the problem was gone.
I updated the mobo drivers and reconnected, but the problem was back. So
now I've changed the power line going to this drive, and that seems to
have righted it, I guess a power problem of sorts after all.
I really don't know anything about power supplies, but I assume I was
trying to pull too much out of one source. Not sure if a higher wattage
PS would solve such problems, but it appears I was managing what I have
rather poorly.
So any chance that I've caused any other problems in the course of all
this? All that rebooting kind of makes me uncomfortable, and I don't
know that this hasn't put undo strain on the PS. It also seems odd that
this problem didn't crop up for several weeks after adding the drive.
On Sat, 10 Mar 2007 23:49:23 -0800, Mark N
<menusbaum@NYETSPAMearthlink.net> wrote:
>The box had never before rebooted until two weeks ago, and the problem
>recurs at least every hour, and sometimes every few seconds - I woke up
>last night to continuous beeping, each time the PC POSTed. The last
>change to the box was several weeks earlier, when I changed optical
>drives and added a hard drive, so I decided to start there. I had been a
>bit concerned about the SATA HD, as I seem to recall that early SATA
>mobos have had some problems, so I unhooked it and the problem was gone.
>I updated the mobo drivers and reconnected, but the problem was back. So
>now I've changed the power line going to this drive, and that seems to
>have righted it, I guess a power problem of sorts after all.
>
>I really don't know anything about power supplies, but I assume I was
>trying to pull too much out of one source.
What else did you have hooked up to the same leads? It is
doubtful you were trying to pull too much, more likely the
connector - drive connection was just flaky for whatever
reason, perhaps the connector just didn't plug in good - it
is a shame everyone is trying to shrink all these connectors
down as small as they can go reliably in a lab environment
then expecting real-world use and products to do as well in
all cases. If they were just running out of room on the
back of a hard drive to fit all the pins I could see it, but
the only problem is short-sighted engineering. Engineering
for ideals that don't hold true as often as the legacy power
connections. I'm being a bit overly critical, usually they
work fine but in some ways it is a step backwards.
>Not sure if a higher wattage
>PS would solve such problems, but it appears I was managing what I have
>rather poorly.
>
>So any chance that I've caused any other problems in the course of all
>this? All that rebooting kind of makes me uncomfortable, and I don't
>know that this hasn't put undo strain on the PS. It also seems odd that
>this problem didn't crop up for several weeks after adding the drive.
An intermittent power connection (to the drive) shouldn't
have been resetting the system when sitting at a bios menu.
Where the connector contacts grossly mangled or defective to
the extent that they might have shorted against each other
temporarily? If not, I would wonder about the drive and PSU
still.
A poor connection could take a while to reveal itself,
particularly so when a marginal connection can foul the
contacts from slight arcing. Hopefully the problem is
solved but you might try to examine the contacts on the
drive, and connector, and give it some time to see if the
problem resurfaces... and if it does, then try another drive
and connector, so you have two mating contacts that weren't
potentially fouling themselves.
>> The box had never before rebooted until two weeks ago, and the problem
>> recurs at least every hour, and sometimes every few seconds - I woke up
>> last night to continuous beeping, each time the PC POSTed. The last
>> change to the box was several weeks earlier, when I changed optical
>> drives and added a hard drive, so I decided to start there. I had been a
>> bit concerned about the SATA HD, as I seem to recall that early SATA
>> mobos have had some problems, so I unhooked it and the problem was gone.
>> I updated the mobo drivers and reconnected, but the problem was back. So
>> now I've changed the power line going to this drive, and that seems to
>> have righted it, I guess a power problem of sorts after all.
>>
>> I really don't know anything about power supplies, but I assume I was
>> trying to pull too much out of one source.
> What else did you have hooked up to the same leads? It is
> doubtful you were trying to pull too much, more likely the
> connector - drive connection was just flaky for whatever
> reason, perhaps the connector just didn't plug in good - it
> is a shame everyone is trying to shrink all these connectors
> down as small as they can go reliably in a lab environment
> then expecting real-world use and products to do as well in
> all cases. If they were just running out of room on the
> back of a hard drive to fit all the pins I could see it, but
> the only problem is short-sighted engineering. Engineering
> for ideals that don't hold true as often as the legacy power
> connections. I'm being a bit overly critical, usually they
> work fine but in some ways it is a step backwards.
>> Not sure if a higher wattage
>> PS would solve such problems, but it appears I was managing what I have
>> rather poorly.
>> So any chance that I've caused any other problems in the course of all
>> this? All that rebooting kind of makes me uncomfortable, and I don't
>> know that this hasn't put undo strain on the PS. It also seems odd that
>> this problem didn't crop up for several weeks after adding the drive.
> An intermittent power connection (to the drive) shouldn't
> have been resetting the system when sitting at a bios menu.
> Where the connector contacts grossly mangled or defective to
> the extent that they might have shorted against each other
> temporarily? If not, I would wonder about the drive and PSU
> still.
> A poor connection could take a while to reveal itself,
> particularly so when a marginal connection can foul the
> contacts from slight arcing. Hopefully the problem is
> solved but you might try to examine the contacts on the
> drive, and connector, and give it some time to see if the
> problem resurfaces... and if it does, then try another drive
> and connector, so you have two mating contacts that weren't
> potentially fouling themselves.
Well, it seems I spoke to soon. After a while I had recurrence of the
reboot problems, even with the new drive disconnected. Then when I
turned on the PC this morning it was back with a vengeance, rebooting
just a matter of seconds after POSTing. After many attempts it managed
to finally start up Windows, and has been stable enough to at least be
typing on this (although it has already rebooted once in the process).
The whole thing doesn't really seem random, it takes time to "warm up"
sufficiently before being able to get farther in the process. Now it's
stable enough to run in Windows for 5-10 minutes anyway.
Anyway, I don't see anything physically wrong on the mobo, and all the
cabling looks fine. I guess I'll try replacing the video card next,
which is easy and would eliminate that idea. Not sure where to go next
after that...
On Sun, 11 Mar 2007 10:24:14 -0700, Mark N
<menusbaum@NYETSPAMearthlink.net> wrote:
>kony wrote:
>> Mark N
> wrote:
>
>>> The box had never before rebooted until two weeks ago, and the problem
>>> recurs at least every hour, and sometimes every few seconds - I woke up
>>> last night to continuous beeping, each time the PC POSTed. The last
>>> change to the box was several weeks earlier, when I changed optical
>>> drives and added a hard drive, so I decided to start there. I had been a
>>> bit concerned about the SATA HD, as I seem to recall that early SATA
>>> mobos have had some problems, so I unhooked it and the problem was gone.
>>> I updated the mobo drivers and reconnected, but the problem was back. So
>>> now I've changed the power line going to this drive, and that seems to
>>> have righted it, I guess a power problem of sorts after all.
>>>
>>> I really don't know anything about power supplies, but I assume I was
>>> trying to pull too much out of one source.
>
>> What else did you have hooked up to the same leads? It is
>> doubtful you were trying to pull too much, more likely the
>> connector - drive connection was just flaky for whatever
>> reason, perhaps the connector just didn't plug in good - it
>> is a shame everyone is trying to shrink all these connectors
>> down as small as they can go reliably in a lab environment
>> then expecting real-world use and products to do as well in
>> all cases. If they were just running out of room on the
>> back of a hard drive to fit all the pins I could see it, but
>> the only problem is short-sighted engineering. Engineering
>> for ideals that don't hold true as often as the legacy power
>> connections. I'm being a bit overly critical, usually they
>> work fine but in some ways it is a step backwards.
>
>>> Not sure if a higher wattage
>>> PS would solve such problems, but it appears I was managing what I have
>>> rather poorly.
>
>>> So any chance that I've caused any other problems in the course of all
>>> this? All that rebooting kind of makes me uncomfortable, and I don't
>>> know that this hasn't put undo strain on the PS. It also seems odd that
>>> this problem didn't crop up for several weeks after adding the drive.
>
>> An intermittent power connection (to the drive) shouldn't
>> have been resetting the system when sitting at a bios menu.
>> Where the connector contacts grossly mangled or defective to
>> the extent that they might have shorted against each other
>> temporarily? If not, I would wonder about the drive and PSU
>> still.
>
>> A poor connection could take a while to reveal itself,
>> particularly so when a marginal connection can foul the
>> contacts from slight arcing. Hopefully the problem is
>> solved but you might try to examine the contacts on the
>> drive, and connector, and give it some time to see if the
>> problem resurfaces... and if it does, then try another drive
>> and connector, so you have two mating contacts that weren't
>> potentially fouling themselves.
>
>Well, it seems I spoke to soon. After a while I had recurrence of the
>reboot problems, even with the new drive disconnected. Then when I
>turned on the PC this morning it was back with a vengeance, rebooting
>just a matter of seconds after POSTing. After many attempts it managed
>to finally start up Windows, and has been stable enough to at least be
>typing on this (although it has already rebooted once in the process).
>The whole thing doesn't really seem random, it takes time to "warm up"
>sufficiently before being able to get farther in the process. Now it's
>stable enough to run in Windows for 5-10 minutes anyway.
>
>Anyway, I don't see anything physically wrong on the mobo, and all the
>cabling looks fine. I guess I'll try replacing the video card next,
>which is easy and would eliminate that idea. Not sure where to go next
>after that...
My son's was doing just that. Re-booting, specially when big programs
were run, but Not a heat issue. After a few things, the only thing
that cured it was to re-install Windows. He didn't lose any programs
doing the re-install, it's ok now.
On 2007-03-11, kony <spam@spam.com> wrote:
> On Sat, 10 Mar 2007 22:44:42 +0000 (UTC), Andrew Smallshaw
><andrews@sdf.lonestar.org> wrote:
>
>>On 2007-03-10, w_tom <w_tom1@usa.net> wrote:
><snip>
>
>>One other point: the UPS on this machine is set to switch in at
>>184 V against a mains rating of 230 V. I hear the relays switch
>>over momentarily maybe a couple of times a week. It may do it more
>>often and I just don't notice. More severe sags can actually last
>>long enough for the alarm to briefly sound - that's much rarer but
>>still maybe every three months on average.
>
> Buy an Active PFC PSU and be done with the UPS wear by
> lowering the voltage setting. It should not need to come on
> at 184V for the computer. Maybe something else you have
> might, but any decent PSU should have no problem, it would
> just lower the max possible output from the PSU but that max
> is within the range of margin it should already have if
> suitably sized for the system.
To be honest I haven't played with the trigger voltage but left it
on the default setting - it probably is higher than it needs to
be. I'll probably leave it that way since artifically lowering
the potential for testing would mean patching a cable and NetBSD
lacks a journaling filesystem for "real life" testing. That makes
unscheduled reboots at best a pain since at the next boot it spends
25 minutes checking the filesystem ;-)
Increased memory voltage? Increases CPU voltage. That is
shotgunning. It learns nothing useful. And if it did fix anything,
it only 'cured symptoms'.
You are still not doing what is said in CSI - follow the evidence.
Trying to fix it rather than first collecting facts only leads to ...
well the previous post described this as experience without basic
knowledge. Due to such speculation, then things that look like
solutions actually solve nothing. Terms like 'spinning your wheels'
apply because advise that would 'follow the evidence' was ignored.
Everything posted implies something in a power supply 'system' has
long been defective. You have used subjective reasoning to declare
that power supply good. Power supply could have been insufficient two
years ago. With age and that optical drive, then the defective power
supply finally created failures. Remember what the meter does? It
may even find problems long before failures happen. Had you used the
meter two years ago, then maybe this problem would have never
occurred.
Worse - you are thinking binary. The world is ternary. Notice
three conditions. a) Power supply good and system works. b) Power
supply defecitve but system works. c) Power supply defective and
system fails. All three exist. Your reasoning has assumed only a)
and c). But again why shotgunning is avoided. But again why those
with only experience sometimes only cure symptoms.
You have established zero items as operational. After so much
effort, nothing is known. Nothing has been accomplished. Get the
meter. In but two minutes, those numbers would have made major
accomplishments. Start a process of learning what is and is not
sufficient. Stop doing the 'try this and try that'. You have
demonstrated only again why shotgunning is not very successful and why
shotgunning takes so much more time. After everything posted, we are
still no closer to a solution because you did not get the meter.
How do we know nothing is being learned. You are trying to fix it.
That comes later. First get the facts. Did you also collect data
from the system (event) log? Another useful fact that long ago might
have identified the problem. Just another example of why we first
collect data long before trying to fix anything.
It is not odd "that this problem didn't crop up for several weeks".
That common occurance is also why shotgunning is so unreliable. But
again, you made an assumption, then drew conclusions from that
assumption. That is also how wild speculation only complicates a
problem. Follow the evidence. Establish what is good. Get the meter
so that every effort results in something other than wild speculation.
So now you will suspect the video card? On what data? Again, more
shotgunning. If another video card changes things, does that mean the
video card is defective? No. It also means the power supply 'system'
is defective, heat is a problem, motherboard bus is defective,
software magically went defective, and ... Stop shotgunning. Or
just telll everyone to go away because you really don't want help.
You have ZERO reasons to blame the video card. ZERO. But you are
shotgunning.
On Mar 11, 3:49 am, Mark N <menusb...@NYETSPAMearthlink.net> wrote:
> Thanks to everyone for their suggestions, and the worthwhile discussion
> on power issues. But I seem to have discovered the problem doing one of
> the things Kony originally suggested. First, what it apparently isn't:
>
> - No high heat readings, and while the suggestion that the readings
> need to be calibrated in order to be determined correct, they are
> relatively the same as they've been since I built the box two years ago.
> So my guess is no heat problems.
>
> - Not a memory voltage issue; I tried that and no change, and also
> tried increasing the Vcore voltage, as the readings have always been at
> 1.44 instead of 1.5, but no help.
>
> - No power issues in my home, lights never dim, and reboots have been
> constant, no more or less at peak and off-peak hours.
>
> - I also noticed that the PC was having performance problems when it
> was up and running, things like video playback skipping and lagging when
> they hadn't before.
>
> The box had never before rebooted until two weeks ago, and the problem
> recurs at least every hour, and sometimes every few seconds - I woke up
> last night to continuous beeping, each time the PC POSTed. The last
> change to the box was several weeks earlier, when I changed optical
> drives and added a hard drive, so I decided to start there. I had been a
> bit concerned about the SATA HD, as I seem to recall that early SATA
> mobos have had some problems, so I unhooked it and the problem was gone.
> I updated the mobo drivers and reconnected, but the problem was back. So
> now I've changed the power line going to this drive, and that seems to
> have righted it, I guess a power problem of sorts after all.
>
> I really don't know anything about power supplies, but I assume I was
> trying to pull too much out of one source. Not sure if a higher wattage
> PS would solve such problems, but it appears I was managing what I have
> rather poorly.
>
> So any chance that I've caused any other problems in the course of all
> this? All that rebooting kind of makes me uncomfortable, and I don't
> know that this hasn't put undo strain on the PS. It also seems odd that
> this problem didn't crop up for several weeks after adding the drive.
w_tom <w_tom1@usa.net> wrote:
> Temperature increase can make a functional but defective computer
> apparent. High reliability equipment gets thermal cycled - sometimes
> called 'burn in' testing - to find defects before failure occurs. Is
> your heatsink incorrect? Well then the computer never did what it
> must do - work inside a room at 100 degrees F and be perfectly happy.
> Your heatsink, if selected or installed by one with engineering
> knowledge such as the manufacturer, is not a problem. However if
> selected by just any computer assembler, then start asking questions
> that were answered by that heatsink manufacturer. What is its degree
> C per watt number? Don't just assume and then start replacing
> things. That is called shotgunning.
>
> Your computer is intermittent. Therefore use a hairdryer on high to
> heat selective parts at temperatures uncomfortable to touch. That is
> a perfectly normal temperature to all working retail electronics.
> This is also when comprehensive hardware diagnostics best find
> failures. At higher temperature, defective electronics then will fail
> consistently. Just another way to find defects and how to have found
> that defect long before your problems were apparent.
>
> Hardware monitor will show changes (a monitor) but is not valid as a
> voltage measurement until calibrated - which is why you need a 3.5
> digit multimeter. A tool so 'complex' as to be sold even in K-mart.
> Any voltage below 3.23, 4.87, or 11.7 is a problem
Wrong, as always.
> and would explain intermittent crashes.
Pig ignorant lie.
> Line voltages should have no effect on a computer. This assumes the
> power supply was purchased with internal functions that were even
> standard 30 years ago. AC electric voltages must drop so low that
> incandescent lamps are at less than 40% intensity and still computer
> both starts and runs 100% OK. Are your lights dimming that low? If
> not, then AC voltage is not (should not be) a problem. Anything that
> a power conditioner or UPS would do to solve a problem is supposed to
> be already inside the power supply. Some power supplies installed by
> those who do not learn electricity are so inferior as to need power
> conditioning. Fix the problem. Don't purchase something many times
> more money to only cure symptoms. Don't cure symptoms. Eliminate the
> problem.
>
> As noted earlier, room temperature and therefore CPU temperatures
> must increase 30 degree F higher; CPU temperature still below
> manufacturer max spec numbers. Again, consult numbers such as
> manufacturer specs. Confirm voltages per limits provided above.
> Eliminate potential suspects completely and then move on to other
> suspects. Hair dryer, multimeter, manufacturer specs ... just some
> simple things that answer questions with yes or no. Answers with
> 'maybe' are wasted time; often from speculation such as AC line noise
> solved by a surge protector or UPS.
>
> Each useful solution is not only recommended. Reasons why it is
> useful is also important. No reasons why? This is why some recommend
> surge protectors or UPS as a solution.
>
> Meanwhile, if I understand this correctly, your problem even occurs
> when only in BIOS. Now we have limited the problem to very few
> suspects. Only a few parts of a motherboard, a tiny part of memory,
> the video controller (maybe), and a power supply 'system'.
>
> On Mar 9, 3:00 pm, Mark N <menusb...@NYETSPAMearthlink.net> wrote:
>> About ten days ago I suddenly started having a problem with my PC
>> rebooting, started from nothing to doing it very regularly, no
>> gradual development into the problem. Sometimes it reboots very
>> quickly, sometimes it will run for an hour or so without any
>> problem. I ran my virus and malware scans, nothing new there, and
>> have blown out the box for dust buildup, checked power connections,
>> memory seating, etc. Don't think it's windows or a hard drive
>> problem, since it sometimes reboots before even getting to the load
>> point. I have a hardware monitor function in the BIOS, and have
>> watched readings there until it reboots, and not much indication of
>> a problem - voltages look okay, CPU temp doesn't get alarmingly
>> high. I was away for a week, came home and the problem started up
>> with a vengeance, couldn't even get Windows loaded, now has backed
>> off a little.
>>
>> My box has an MSI K8N Neo Platinum mobo, Athlon64 3400+ proc, 1 gig
>> Corsair performance memory, ATI 800XT AIW, Enermax 420W PS, XP SP2.
>> Only recent hardware change was swapping out the optical drive and
>> adding a new SATA hard drive a number of weeks ago (now have three,
>> the others EIDE); everything worked well for quite a while after.
>> The rest is about two years old, last rebuild. I did move some
>> cabling around while doing the changes, and I noticed that one cable
>> might have been contacting the CPU fan a bit, although not stopping
>> it or causing a lot of noise. There were some occasional odd noises
>> just before the reboot problem started, and I was a bit concerned
>> about a hard drive going south at that point, but may have been the
>> fan. Nothing lately, though.
>>
>> I assume first it's a heat problem, but the box is big and cool and
>> all fans working. I've been a little concerned about the CPU fan, so
>> thinking of replacing that (retail cooler); I'm not sure if it's
>> always spinning up faster as the temperature rises. It doesn't seem
>> to get very hot, usually first readings are around 47 degrees C,
>> work up over 50, the fan spins up faster around 55 and pushes it
>> down a few degrees, and sometimes the reading just before a reboot
>> is just 50 or a bit more. Not sure how accurate or delayed those
>> readings are, though. Next thought is the PS, but no unusual
>> readings there, with the same caveats on those.
>>
>> Any ideas on what's happening and fixes? I haven't done that much
>> yet, but this is a new one for me and has me a bit stumped. Thanks
>> in advance for any assistance.
Bare faced lie, most obviously with the minimum rail voltages you plucked from your arse.
> Experience alone (without fundamental facts and numbers)
> results in junk science reasoning - also called speculation.
Your minimum rail voltages in spades.
> That guess on illumination is just that - speculation.
Your minimum rail voltages in spades.
> A computer must work just fine even when bulb illumination drops to below 40%.
Pig ignorant drivel. You've plucked that out of your arse too.
> Formulas for numbers of voltage and illumination are an industry
> standard - see IES Handbook. Experience alone does not provide this.
Pity its completely irrelevant to what mains voltage the system will still work fine at.
> Switching power supply 'system' makes those AC electric problems
> irrelevant as even defined by another industry standard (CBEMA) of 30
> years ago. Industry standard numbers demonstrate why all appliances
> work just fine without UPSes or power conditioners. Computer supplies
> typically are even more resilient. How many other household
> appliances are failing more frequently? Some must be if AC electric is
> reason for failure as Andrew speculates. More numbers from both
> standards and experience - one needs both - are provided below.
More of your drivel, actually.
> Your AC voltages must maintain specific limits at different points
> in household distribution. 230 volts must not drop below 205 volts.
> Yes, another standard. Sometimes voltage does drop lower.
Funny that.
> Then those with both experience and knowledge locate
> wiring problems. They don't install power conditioning.
Plenty do when the mains isnt as good as it should be.
> Meanwhile a 230 volts UPS may flip to battery backup mode typically
> at 200 volts. (Yours trips at an untypically low 185 volts - well look
> how much lower all computers must work so that your UPS can trip at
> 185). If Andrews' UPS is tripping daily, experience and the numbers says
> Andrews should identify a marginal wiring problem - maybe a loose screw.
Or a lousy mains supply.
> Since Andrew only uses experience, then Andrew considers
> acceptable what is really unacceptable. Just another reason
> why experience without learning fundamental technology
> results in erroneous conclusions.
Your minimum rail voltages in spades.
> 230 volt power supplies must work just fine with 100% load when AC
> voltage is even lower - 180 VAC. This even stated in Intel ATX standards.
Intel doesnt set the ATX standards.
> Does Andrew still think anything posted was arbitrary? I don't do arbitrary.
You clearly do with those stupid minimum acceptible rail voltages
which arent anything like what the ATX standard says.
> For Mark N and the bottom line: a computer must work just fine even
> when incandescent lamps dim to 40% intensity. These both from
> industry standard numbers and from too many decades of experience.
Irrelevant to what the ATX standard requires.
> If PSU voltages are too low and cause a reboot, then problem
> is apparent in multimeter numbers defined previously or in
> http://tinyurl.com/yvf9vh .
> Meter numbers will either report voltages just fine (so we move on to
> other suspects as defined by Kony) or report power supply 'system' as
> reason for reboot.
Wrong, as always.
> As Kony also notes:
>> If the temp never gets above 55 it's cool enough
> System also must be stable when air temperatures are raised another
> 30 degree F. Heat causing failure in a 70 degree room - then hardware
> is obviously defective. Heat typically is a great diagnostic tool to
> find defects; not something to be cured. Increased heat can make
> reboots more frequent. Again heat used to identify a defect.
> Obvious symptoms such as bulging capacitors may also find a
> problem. But again, reason for failure is definitive - therefore a
> useful tool to find defect.
Meaningless waffle.
> Fact that reboot occurs even when only in BIOS is another useful
> fact that limits problem to very few suspects as posted previously.
> Some recommend UPSes or power conditioners when basic knowledge (ie
> all those industry standards) is not first learned. Experience alone
> often results only in speculation. If a UPS or power conditioner
> 'fixes' the problem, then power supply 'system' is probably defective,
> or incandescent lamps are dimming excessively and obviously.
Pathetic.
> How to find reasons for reboot? Procedure also provided in
> http://tinyurl.com/yvf9vh
> and two minutes exonerates or condemns power supply
> 'system' (including AC voltage problems).
Bare faced lie, regardless of how often its repeated.
> Also useful are what those voltages do when system reboots.
> If problem is not in the power supply 'system' (as meter will report),
Not necessarily.
> then move on to other suspects.
No thanks.
> Don't just speculate which is what happens when experience
> is not tempered by fundamental knowledge - ie the above numbers.
> Get numbers to know what is and is not working - without speculation.
Your minimum rail voltages are pure speculation.
> Experience without those standards and numbers
> creates only speculation. I don't do arbitrary.
Bare faced lie with your minimum rail voltages.
> On Mar 10, 5:44 pm, Andrew Smallshaw <andr...@sdf.lonestar.org> wrote:
>> Yes, this amount of drop could be perfectly reasonable. Even if
>> we accept your figures (which sound arbitrary to me, as did your
>> minimum voltages) a 60% dip in illumination is an unexceptional
>> sag. Recall that the human eye is logarithmic in behaviour - a
>> 60% drop at normal levels of indoor illumination would be _perceived_
>> as a drop in the region of 10%. When you consider that it ceases
>> to be impossible and more a reasonably common occurance.
>>
>> I do accept in part your comments about the filtering capability
>> of switched mode power supplies, they do have a certain amount of
>> resilience built in. But that is mainly either a function of the
>> way they work (as in the case of tolerance to variations in supply
>> voltage) or a minimum level to ensure proper operation for at least
>> the majority of the time (as is the case for protection against
>> transients). Both have their limits. A UPS or surge protector
>> mitigates (not so) exceptional events over and above those expected
>> in normal operation.
>>
>> One other point: the UPS on this machine is set to switch in at
>> 184 V against a mains rating of 230 V. I hear the relays switch
>> over momentarily maybe a couple of times a week. It may do it more
>> often and I just don't notice. More severe sags can actually last
>> long enough for the alarm to briefly sound - that's much rarer but
>> still maybe every three months on average.
>> ...
>>
>> So, you can immediately identify the cause of any problem without
>> first running through a list of hypotheses to be considered and
>> eliminated?
>> ...
>>
>> Why did I suggest the power as a _possible_ cause (unlike you I do
>> not claim to have a difinitive answer, I merely offered a suggestion
>> based on experience)? Well, we're not talking about a clear and
>> apparent equipment failure here, so the first question I'd ask is
>> "So what's changed?" This is basic troubleshooting methodology.
>>
>> If we take the OP at their word then nothing has changed to the
>> system so the next step is to look at external factors, the mains
>> being one of them. If you refer back to my original post I did
>> ask about any factors that the poster may have known about that
>> could affect the local power supply, although of course the OP may
>> not be aware of routine maintenance or upgrade work being carried
>> out.
>> ...
>>
>> You asked for a justification for my suggestion regarding the mains
>> which I was happy to give. Now, given that the system hasn't
>> changed, why do you suspect it has suddenly started to suffer
>> through some kind of thermal stress?
On Mar 11, 2:48 pm, "Rod Speed" <rod.speed....@gmail.com> wrote:
> w_tom <w_t...@usa.net> wrote:
> > Nothing arbitrary was posted.
>
> Bare faced lie,
Snipped all the comments.
I am new to this forum and was enjoying the interchange of ideas when
Rod proceded to make comment and not help.
DO I need to ignore anything from this person?
Now to the problem at hand....
I have worked on computers for many years.
Flaky PSU's are sometimes just that, flaky.
They do not cause a failure, or reboot until it happens.
Switching power feeds to the HD temporarily cured it.
This really indicates a PSU problem.
However, swapping out, to cure, is not very specific,as the other
helpers have noted.
On Sun, 11 Mar 2007 12:28:24 -0700, mhaase-at-springmind.com
<mhaase-at-springmind.com@> wrote:
>On Sun, 11 Mar 2007 10:24:14 -0700, Mark N
><menusbaum@NYETSPAMearthlink.net> wrote:
>
>
>>
>>Well, it seems I spoke to soon. After a while I had recurrence of the
>>reboot problems, even with the new drive disconnected. Then when I
>>turned on the PC this morning it was back with a vengeance, rebooting
>>just a matter of seconds after POSTing. After many attempts it managed
>>to finally start up Windows, and has been stable enough to at least be
>>typing on this (although it has already rebooted once in the process).
>>The whole thing doesn't really seem random, it takes time to "warm up"
>>sufficiently before being able to get farther in the process. Now it's
>>stable enough to run in Windows for 5-10 minutes anyway.
>>
>>Anyway, I don't see anything physically wrong on the mobo, and all the
>>cabling looks fine. I guess I'll try replacing the video card next,
>>which is easy and would eliminate that idea. Not sure where to go next
>>after that...
>
>
>If when you say:
>
>> I don't see anything physically wrong on the mobo
>
>You specifically looked for bad/swollen capacitors, then my money's
>still on the Power Supply.
>
>M
>
Agreed, I'd think that more likely than the video card.
On Sun, 11 Mar 2007 21:26:38 +0000 (UTC), Andrew Smallshaw
<andrews@sdf.lonestar.org> wrote:
>> Buy an Active PFC PSU and be done with the UPS wear by
>> lowering the voltage setting. It should not need to come on
>> at 184V for the computer. Maybe something else you have
>> might, but any decent PSU should have no problem, it would
>> just lower the max possible output from the PSU but that max
>> is within the range of margin it should already have if
>> suitably sized for the system.
>
>To be honest I haven't played with the trigger voltage but left it
>on the default setting - it probably is higher than it needs to
>be. I'll probably leave it that way since artifically lowering
>the potential for testing would mean patching a cable and NetBSD
>lacks a journaling filesystem for "real life" testing. That makes
>unscheduled reboots at best a pain since at the next boot it spends
>25 minutes checking the filesystem ;-)
There shouldn't be any testing necessary if the PSU is
already spec'd for a 110-220+ range, it should be expected
to run equally well already... if it didn't, it would be as
prudent to test it again at it's present voltage in case it
had degraded in general, not-volt-specific, function.
mlinsenb@dakotacom.net wrote:
> On Mar 11, 2:48 pm, "Rod Speed" <rod.speed....@gmail.com> wrote:
>>
>> Bare faced lie,
>
> Snipped all the comments.
>
> I am new to this forum and was enjoying the interchange of ideas
> when Rod proceded to make comment and not help.
>
> DO I need to ignore anything from this person?
Yes. He is a known troll. If you shift to a real newsreader you
can just PLONK him and his mouthings will no longer annoy you
(except when quoted by someone else).
--
Chuck F (cbfalconer at maineline dot net)
Available for consulting/temporary embedded and systems.
<http://cbfalconer.home.att.net>
>On Mar 11, 2:48 pm, "Rod Speed" <rod.speed....@gmail.com> wrote:
>> w_tom <w_t...@usa.net> wrote:
>> > Nothing arbitrary was posted.
>>
>> Bare faced lie,
>
>Snipped all the comments.
>
>I am new to this forum and was enjoying the interchange of ideas when
>Rod proceded to make comment and not help.
>
>DO I need to ignore anything from this person?
It would be easier.
>
>Now to the problem at hand....
>
>I have worked on computers for many years.
>Flaky PSU's are sometimes just that, flaky.
>They do not cause a failure, or reboot until it happens.
>Switching power feeds to the HD temporarily cured it.
>This really indicates a PSU problem.
>However, swapping out, to cure, is not very specific,as the other
>helpers have noted.
>
>Please take the time to be thorough.
>YB
If the PSU problem is intermittent, you're left detecting it
exactly when it happens. Do you have the facilities to do
this? For example an o'scope or fast logging multimeter,
though of course it can't be hooked up to the PC that is
resetting itself to do logging.
You might unplug the PSU from AC for a few minutes and then
open, examine it. With luck you might find visual
indication of a failure like vented capacitors, or if you
have a multimeter you can check things like shorted/open
rectifiers or switching transistors, cold solder joints.
Otherwise such an intermittent problem still leaves you
waiting to catch it happening again, as the parts can't be
totally unworking yet to be able to turn the system back on
at all.
In other words, there are only two real alternatives, either
you have the tools, ability, and patience to take apart your
PSU and apply various load and temp conditions to it while
logging the output quality, or you don't and can only test
or look for basic things before swapping in a different PSU.
w_tom wrote:
> Increased memory voltage? Increases CPU voltage. That is
> shotgunning. It learns nothing useful. And if it did fix anything,
> it only 'cured symptoms'.
>
> You are still not doing what is said in CSI - follow the evidence.
> Trying to fix it rather than first collecting facts only leads to ...
> well the previous post described this as experience without basic
> knowledge. Due to such speculation, then things that look like
> solutions actually solve nothing. Terms like 'spinning your wheels'
> apply because advise that would 'follow the evidence' was ignored.
>
> Everything posted implies something in a power supply 'system' has
> long been defective. You have used subjective reasoning to declare
> that power supply good. Power supply could have been insufficient two
> years ago. With age and that optical drive, then the defective power
> supply finally created failures. Remember what the meter does? It
> may even find problems long before failures happen. Had you used the
> meter two years ago, then maybe this problem would have never
> occurred.
>
> Worse - you are thinking binary. The world is ternary. Notice
> three conditions. a) Power supply good and system works. b) Power
> supply defecitve but system works. c) Power supply defective and
> system fails. All three exist. Your reasoning has assumed only a)
> and c). But again why shotgunning is avoided. But again why those
> with only experience sometimes only cure symptoms.
>
> You have established zero items as operational. After so much
> effort, nothing is known. Nothing has been accomplished. Get the
> meter. In but two minutes, those numbers would have made major
> accomplishments. Start a process of learning what is and is not
> sufficient. Stop doing the 'try this and try that'. You have
> demonstrated only again why shotgunning is not very successful and why
> shotgunning takes so much more time. After everything posted, we are
> still no closer to a solution because you did not get the meter.
>
> How do we know nothing is being learned. You are trying to fix it.
> That comes later. First get the facts. Did you also collect data
> from the system (event) log? Another useful fact that long ago might
> have identified the problem. Just another example of why we first
> collect data long before trying to fix anything.
>
> It is not odd "that this problem didn't crop up for several weeks".
> That common occurance is also why shotgunning is so unreliable. But
> again, you made an assumption, then drew conclusions from that
> assumption. That is also how wild speculation only complicates a
> problem. Follow the evidence. Establish what is good. Get the meter
> so that every effort results in something other than wild speculation.
>
> So now you will suspect the video card? On what data? Again, more
> shotgunning. If another video card changes things, does that mean the
> video card is defective? No. It also means the power supply 'system'
> is defective, heat is a problem, motherboard bus is defective,
> software magically went defective, and ... Stop shotgunning. Or
> just telll everyone to go away because you really don't want help.
> You have ZERO reasons to blame the video card. ZERO. But you are
> shotgunning.
My, but you seem to enjoy being superior. Understand that I appreciate
the help, though. To this point I've not done all that much, just tried
to observe what has been happening and considering suggestions. What I
can easily do that might eliminate at least some long odds possibilities
I have done like (yes) swapping out the video card and running the pair
of memory modules by themselves, and it seems those possibilities can
now be eliminated. I have no idea how good the power supply is, and have
no particular reason to believe it's good. I do have an old power supply
that I've considered trying, but not sure that the connectors are the
necessary ones. Just haven't gotten to it yet. Regarding the voltage
meter, I have no idea how to use one, but it seems a good idea.
Understand that I know very little about electronics, and I'm hardly a
PC expert. I built the PC originally to obtain a better understanding of
the things, have upgraded it significantly, and have followed my nose
successfully through all the problems I've had so far, which fortunately
have mostly been on the software side, and have learned a lot in the
process. But, again, I ain't no expert.
The power supply seems like an increasingly good candidate to me. The
heat readings, accurate in absolute terms or not, and the rebooting
behavior suggest that it's not a heat problem to me. I have no idea what
would be evidence of a mobo failure, beyond visibly bad capacitors, so
maybe that's left when other things have been eliminated. I can't see
any point to taking a hair dryer to the thing, given the wonky behavior
now, and I can't turn back the clock to when I first rebuilt the thing.
In the end I may have to either start swapping out parts, based on best
guesses, or bring it to someone who does understand the things and has
the parts to do more thorough testing.
So if you feel inclined to give me a few pointers on how to test the PS,
I'm all ears...
Apparently an emotion is perceived. I make no effort to be
politically correct. Instead are posted straight, blunt, and honest
facts. Have no idea why one might confuse blunt and honest reasons
with a perceived emotion. Posted was how to solve your problem ASAP -
and reasons why.
A meter is so complex that it is sold in K-mart. I keep making that
point because so many fear to learn things new. How could you change
CPU voltages when that is clearly more complex and (for all you know)
could damage the processor (a concept called overstress)? For
example, it you found a defective video card, well, that may only be a
function of a defective supply. IOW you still have no definitive fact
because the computer's foundation is completely unknown AND suspect.
Labor resulted in no definitive results.
Anything or everything can appear intermittent if a power supply
'system' is suspect. If shotgunning, then little that is definitive
is learned. Do you plane doors inside a house when its foundation is
crumbling? Or do you fix the foundation? A defective power supply
'system' is the one item that can cause everything to appear
defective.
Why fear something new only because it is new? Others with only a
high school education use a meter - which is why a multimeter is sold
even in K-mart. An Ipod is more complex. Should we also fear Ipods?
Get the meter. Don't second guess the meter (or a hairdryer).
Shotgun with another power supply? Then previous posts were not
comprehended. Remember so many reasons why you need the meter? A
perfectly good power supply may fail in this system - no definitive
answer obtained. Making changes may make the problem exponentially
more complex. A slew of other reasons previously posted says use the
meter. Two trivial minutes provides useful information both to you
and to those offering assistance. No numbers only starves your help.
What would be evidence of a motherboard failure? You nor I care
yet. Break a problem down into parts; then diagnosing those parts -
piece by piece. Later we can explain why a hairdryer (as we do even
with aerospace hardware) is a powerful tool. You don't yet have a
clue as to why that tool is so useful; no do we yet care. Forget the
motherboard as any reason for failure. KISS. Get the meter.
You cannot eliminate a single hardware possibility until we have
established the foundation. Things you claim to have eliminated are
still suspects because what you did could not yet provide a
'definitive' answer. Only answer worth anything is a 'definitive'
answer.
Best way to test a power supply has been provided twice over.
Disconnect nothing. Swap nothing. Even leave the optical drive
connected. Get the meter. Do what was posted above or in "When your
computer dies without warning....." at: http://tinyurl.com/yvf9vh
And then post those numbers (regardless of what you have concluded)
because those numbers may also contain other useful facts. You have no
idea yet the power of what is recommended. Learn some new tricks.
But more important, appreciate the power of 'breaking a problem down
into parts' AND how to 'follow the evidence'. Amazing how many people
do not understand that principle even when watching 'CSI' every week.
Instead they want to fix something based only on guesses. Even car
mechanics get fired for diagnosing that way.
Kony also demonstrated the same concept. Do you replace a
motherboard only because motherboard might have bad capacitors? Of
course not. First look at those capacitors - collect facts. Change
nothing until a reason exists - ie bulging caps.
Well, my car is burning oil; leaving a trail of smoke. Maybe it's
the gasoline. I will try another brand. That might fix it. Your
response to spontaneous reboots used the exact same flawed reasoning.
Get the meter. Measure those voltages without disconnecting or
removing anything.
On Mar 12, 1:30 am, Mark N <menusb...@NYETSPAMearthlink.net> wrote:
> My, but you seem to enjoy being superior. Understand that I appreciate
> the help, though. To this point I've not done all that much, just tried
> to observe what has been happening and considering suggestions. What I
> can easily do that might eliminate at least some long odds possibilities
> I have done like (yes) swapping out the video card and running the pair
> of memory modules by themselves, and it seems those possibilities can
> now be eliminated. I have no idea how good the power supply is, and have
> no particular reason to believe it's good. I do have an old power supply
> that I've considered trying, but not sure that the connectors are the
> necessary ones. Just haven't gotten to it yet. Regarding the voltage
> meter, I have no idea how to use one, but it seems a good idea.
> Understand that I know very little about electronics, and I'm hardly a
> PC expert. I built the PC originally to obtain a better understanding of
> the things, have upgraded it significantly, and have followed my nose
> successfully through all the problems I've had so far, which fortunately
> have mostly been on the software side, and have learned a lot in the
> process. But, again, I ain't no expert.
>
> The power supply seems like an increasingly good candidate to me. The
> heat readings, accurate in absolute terms or not, and the rebooting
> behavior suggest that it's not a heat problem to me. I have no idea what
> would be evidence of a mobo failure, beyond visibly bad capacitors, so
> maybe that's left when other things have been eliminated. I can't see
> any point to taking a hair dryer to the thing, given the wonky behavior
> now, and I can't turn back the clock to when I first rebuilt the thing.
> In the end I may have to either start swapping out parts, based on best
> guesses, or bring it to someone who does understand the things and has
> the parts to do more thorough testing.
>
> So if you feel inclined to give me a few pointers on how to test the PS,
> I'm all ears.
Apologies for the delay in repsonding to this but my news server
seems to be expiring articles very quickly at the moment. Methinks
we're going down a blind alley with this discussion of lighting
but what the hell...
On 2007-03-11, w_tom <w_tom1@usa.net> wrote:
> Nothing arbitrary was posted. Experience alone (without fundamental
> facts and numbers) results in junk science reasoning - also called
> speculation. That guess on illumination is just that - speculation.
My 10% figure for perceived dip in illumination wasn't plucked from
thin air. As an amatuer astronomer I'm well aware of the eye's
limitations. I consulted a book on optics from the shelf - the
eye is pretty fundamental and receives much coverage. The figure
was taken from a graph. I've found something similar online at:
A filament light bulb will typically reach 40% rated luminosity at
around 0.76x rated voltage [1]. In my 230 V example this works
out to 175 V - that's not a country mile from the 184 V my UPS
trips at, and it's above the unit's less sensitive settings.
> Your AC voltages must maintain specific limits at different points
> in household distribution. 230 volts must not drop below 205 volts.
True, but the 10% tolerance applies on a continuous basis only, it
does not cover transients. There's no question that the voltage
drops below this as the UPS does trip.
> Meanwhile a 230 volts UPS may flip to battery backup mode typically
> at 200 volts. (Yours trips at an untypically low 185 volts - well look
> how much lower all computers must work so that your UPS can trip at
> 185).
Like most UPSs aimed at the computer market, its trip voltage is
user configurable, in this case over the range 160-196 V. The 184
(presumably nominal) is simply the stock setting.
> If Andrews' UPS is tripping daily, experience and the numbers
> says Andrews should identify a marginal wiring problem - maybe a loose
> screw. Since Andrew only uses experience, then Andrew considers
> acceptable what is really unacceptable. Just another reason why
> experience without learning fundamental technology results in
> erroneous conclusions.
I very much doubt a wiring problem. Such a "loose screw" would
have different behaviour and either not manifest itself, or have
a much longer (probably although not necessarily permament) effect.
In any case the electrics are reasonably modern. Oh, and there's
been a time served electrician (my father) living in the house ever
since it was built.
Added to that, it's strange how these 'wiring problems' suddenly
become a lot more apparent in thunderstorms. Or gales for that
matter.
On Mar 14, 6:38 pm, Andrew Smallshaw <andr...@sdf.lonestar.org> wrote:
> True, but the 10% tolerance applies on a continuous basis only, it
> does not cover transients. There's no question that the voltage
> drops below this as the UPS does trip.
Power supply must work just fine when line voltage drops by 25%
continuously. It also must work just fine when voltages drop even
lower for less time. This is what it must do. Therefore power supply
will be even more resilient. For example, when voltage is lost for
maybe 20 milliseconds, then PC must work uninterrupted.
Why is that number important? Even UPS relays take 10+ milliseconds
to switch from a 'direct to AC mains' connection to 'battery backup
power' connection.
If AC electric has anomalies causing that unacceptable voltage drop,
then other appliances (ie microwave clock, VCR) will be flashing every
day - maybe within hours. Are you daily resetting the microwave
clock? Then problem is not inside a computer. Don't cure symptoms.
Fix the problem - defective AC wiring; defective utility, etc.
Computers are so robust that no daily power changes should ever affect
the computer.
Having said this, homeowners with AC receptacles connected by a rear
'push in' connection are all but asking for future problems.
Receptacles should have wires wrapped around screws. Simply remove
the cover plate to inspect. Wire should be obviously wrapped and
tightened by screws.
If AC electric creates a need for a UPS, then fix the grossly
unacceptable problem. UPS would only cure symptoms. UPS is not for
making hardware more reliable. UPS is for blackouts or extreme (long)
brownouts; for data protection.
On Wed, 14 Mar 2007 22:38:08 +0000 (UTC), Andrew Smallshaw
<andrews@sdf.lonestar.org> wrote:
>My 10% figure for perceived dip in illumination wasn't plucked from
>thin air.
Regardless, it is not expected that a computer SMPS will
have any problems with AC voltage depression if there are no
observed problems with anything else at the location. If
one wants to do a lot of advanced measurements, great, but
as well it would be to just measure the output of the PSU
itself or try another one.
On Mar 14, 8:33 pm, mhaase-at-springmind.com <mhaase-at-
springmind.com@> wrote:
> ...
> My question is about detecting super-fast variations in output voltage
> from a bad PSU. I've come across power supplies that will cause the
> machine they're installed in to randomly reboot (confirmed this by
> installing the same PSU in a different computer and seeing the same
> reboot problem).
>
> Now I assume this is happening because something in the PSU is causing
> some kind of momentary power swing/fluctuation/drop/etc at it's
> output. I'm guessing it's momentary/super quick, because the meter
> shows all is fine.
>
> So my question is: Is there anyway to use a meter to check for this
> kind of failure?
Notice layers of filtering between fast transient generators and the
power supply. First, ceramic capacitors are scattered all over the
board; adjacent to all fast transient generators to bypass such
currents right at the source. More filtering electrolytics where
power is applies to the board. Then more inside the power supply.
Those fast transients are made irrelevant by the fitlering. However
slower frequency voltages also are not measured by most meters - often
called ripple voltage.
Notice numbers provided for voltages. 3.23, 4.87, and 11.7. These
are higher than what the actual voltages can be (3.135, 4.75, and
11.4). Voltages measured between those two values can actually be
dipping repeatedly below those lower limts. Above higher acceptable
numbers compensate for how meters work and for how power supplies
respond to higher frequency voltages that most meters cannot measure.
Add layers of filtering that must exist for all systems and those
microsecond type transients are made completely irrelevant.
> If the PSU problem is intermittent, you're left detecting it
> exactly when it happens. Do you have the facilities to do
> this? For example an o'scope or fast logging multimeter,
> though of course it can't be hooked up to the PC that is
> resetting itself to do logging.
>
> You might unplug the PSU from AC for a few minutes and then
> open, examine it. With luck you might find visual
> indication of a failure like vented capacitors, or if you
> have a multimeter you can check things like shorted/open
> rectifiers or switching transistors, cold solder joints.
> Otherwise such an intermittent problem still leaves you
> waiting to catch it happening again, as the parts can't be
> totally unworking yet to be able to turn the system back on
> at all.
>
> In other words, there are only two real alternatives, either
> you have the tools, ability, and patience to take apart your
> PSU and apply various load and temp conditions to it while
> logging the output quality, or you don't and can only test
> or look for basic things before swapping in a different PSU.
Well, I've eliminated the PSU as a source of the rebooting problem,
swapped it out for another and the problem remains exactly the same.
Still rebooting regularly, sometimes very quickly before the BIOS
routine is fully run, sometimes after it's been running for an hour or
so, but always a problem and not noticeably getting worse. In the course
of installing the PS I rechecked all the connections and rechecked the
mobo visually, nothing new. Not sure where to go next...
On Sat, 17 Mar 2007 10:54:15 -0700, Mark N
<menusbaum@NYETSPAMearthlink.net> wrote:
>Well, I've eliminated the PSU as a source of the rebooting problem,
>swapped it out for another and the problem remains exactly the same.
>Still rebooting regularly, sometimes very quickly before the BIOS
>routine is fully run, sometimes after it's been running for an hour or
>so, but always a problem and not noticeably getting worse. In the course
>of installing the PS I rechecked all the connections and rechecked the
>mobo visually, nothing new. Not sure where to go next...
The thread is now pretty long and I've forgotten some
details but have you tried another video card? If not I
would try that next if you had another available - even some
really old PCI card, if for no other reason than that it is
easier (and cheaper, you can get such an old ~2MB PCI card
from a mom-n-pop computer shop or online surplus or ebay for
about $5 or less, if not free in some web for-sale forums
but for shipping cost), quicker, less expensive than buying
a replacement motherboard.
Similarly you can try ruling out other parts subtractively,
disconnecting them from the system and seeing if the problem
persists. I assume there are no unused motherboard
standoffs shorting the back of the case or loose wires or
memory, etc... some things are hard to speculate about
without having the system in front of us or knowing all
details of it's history. You could also pull the board out
and try it in a minimal config on a desktop - not on
ESD-safe surface as that conducts electricity on the back of
the board.
kony wrote:
> Mark N wrote:
>
>> Well, I've eliminated the PSU as a source of the rebooting problem,
>> swapped it out for another and the problem remains exactly the same.
>> Still rebooting regularly, sometimes very quickly before the BIOS
>> routine is fully run, sometimes after it's been running for an hour or
>> so, but always a problem and not noticeably getting worse. In the course
>> of installing the PS I rechecked all the connections and rechecked the
>> mobo visually, nothing new. Not sure where to go next...
> The thread is now pretty long and I've forgotten some
> details but have you tried another video card? If not I
> would try that next if you had another available - even some
> really old PCI card, if for no other reason than that it is
> easier (and cheaper, you can get such an old ~2MB PCI card
> from a mom-n-pop computer shop or online surplus or ebay for
> about $5 or less, if not free in some web for-sale forums
> but for shipping cost), quicker, less expensive than buying
> a replacement motherboard.
>
> Similarly you can try ruling out other parts subtractively,
> disconnecting them from the system and seeing if the problem
> persists. I assume there are no unused motherboard
> standoffs shorting the back of the case or loose wires or
> memory, etc... some things are hard to speculate about
> without having the system in front of us or knowing all
> details of it's history. You could also pull the board out
> and try it in a minimal config on a desktop - not on
> ESD-safe surface as that conducts electricity on the back of
> the board.
I already tried another video card, no change. I've checked the memory,
including running memtest86, no problems there. Given that reboots can
happen very early in the boot cycle, that doesn't leave much. Power
supply is fine. I have a sound card and dial-up modem as PCI cards, and
I guess I could pull those. I haven't pulled the mobo yet, but perhaps
worth pulling it out just to make sure nothing's under it.
Strange behavior in the last 24 hours. Seemed like it was close to being
done, rebooting rapidly and then just POSTing with long beeps, then last
night it booted upo and stayed running. After a couple hours I restarted
after reconnecting my DSL modem, and it booted fine again. A couple
hours later I went to bed and left it on, it went into hibernation fine,
and started up fine this morning, ran fine for about four hours before I
turned it off. Came home tonight and right back into the same old reboot
pattern...
spontaneous reboot problem 
Linear Mode
