Hi, kinda new to all this stuff. I currently want to change an old PSU
unit in a computer to a higher rated one. However when I checked the
spec of the old PSU it had a -5V output, now all the PSU I have
looked at dont have this output , so I am left a bit worried.
So will a newer PSU without a -5V work ( or if it stops some stuuf
working what? - also what exactly is the -5V used for???) or do I
have to try find a PSU with a -5V output??
Glendon wrote:
> Hi, kinda new to all this stuff. I currently want to change an old PSU
> unit in a computer to a higher rated one. However when I checked the
> spec of the old PSU it had a -5V output, now all the PSU I have
> looked at dont have this output , so I am left a bit worried.
>
> So will a newer PSU without a -5V work ( or if it stops some stuuf
> working what? - also what exactly is the -5V used for???) or do I
> have to try find a PSU with a -5V output??
>
> Thanks,
>
> a confused new guy!!!
>
Some old chips needed a negative supply,
newer chips ,when they need it , generate
this on-chip, so,no you dont need -5V.
Glendon wrote:
> Hi, kinda new to all this stuff. I currently want to change an old PSU
> unit in a computer to a higher rated one. However when I checked the
> spec of the old PSU it had a -5V output, now all the PSU I have
> looked at dont have this output , so I am left a bit worried.
>
> So will a newer PSU without a -5V work ( or if it stops some stuuf
> working what? - also what exactly is the -5V used for???) or do I
> have to try find a PSU with a -5V output??
>
> Thanks,
>
> a confused new guy!!!
If you give us the make and model of your motherboard, we could find
out whether or not your board requires it or not.
Many boards don't need one, but I'd hate for yours to be one that does,
and you wind up with a dead mb because of an assumption. It's unlikely
you'd damage anything, but i'd perfer to actually verify that first.
>> Hi, kinda new to all this stuff. I currently want to change an old PSU
>> unit in a computer to a higher rated one. However when I checked the
>> spec of the old PSU it had a -5V output, now all the PSU I have
>> looked at dont have this output , so I am left a bit worried.
>>
>> So will a newer PSU without a -5V work ( or if it stops some stuuf
>> working what? - also what exactly is the -5V used for???) or do I
>> have to try find a PSU with a -5V output??
>>
>> Thanks,
>>
>> a confused new guy!!!
>>
> Some old chips needed a negative supply,
> newer chips ,when they need it , generate
> this on-chip, so,no you dont need -5V.
If his system is older, as it seems to be, he may indeed need the -5v.
Without knowing specifics, we're just guessing.
UCLAN <nomail@thanks.org> wrote
> Sjouke Burry wrote
>>> Hi, kinda new to all this stuff. I currently want to change an old
>>> PSU unit in a computer to a higher rated one. However when I
>>> checked the spec of the old PSU it had a -5V output, now all the
>>> PSU I have looked at dont have this output , so I am left a bit worried.
>>> So will a newer PSU without a -5V work ( or if it stops some stuuf
>>> working what? - also what exactly is the -5V used for???) or do I
>>> have to try find a PSU with a -5V output??
>>> a confused new guy!!!
>> Some old chips needed a negative supply,
>> newer chips ,when they need it , generate
>> this on-chip, so,no you dont need -5V.
> If his system is older, as it seems to be, he may indeed need the -5v.
> Without knowing specifics, we're just guessing.
Not much of a guess, I cant think of anything that
uses an ATX supply that ever used that rail.
I have bad news guys and will proably get loads of grief for it. Its
an old Dell!!!!!!!!!!!, I have read bits and bobs that the -5V is
probably only used for the ISA slot (not used by me or anyone I
think!!!) and the onboard sound (Im guessing an old sound card
installed on an empty PCI slot would overcome this?). Im just not in
a position to buy a whole new setup and would rather just get a new
ATX PSU (which I can then use in the future) and a $5 Dell - ATX
power adapter that is available.
The main I dont want is to get smoke coming out of the machine!!!!!!!
Glendon wrote:
> I have bad news guys and will proably get loads of grief for it. Its
> an old Dell!!!!!!!!!!!, I have read bits and bobs that the -5V is
> probably only used for the ISA slot (not used by me or anyone I
> think!!!) and the onboard sound (Im guessing an old sound card
> installed on an empty PCI slot would overcome this?). Im just not in
> a position to buy a whole new setup and would rather just get a new
> ATX PSU (which I can then use in the future) and a $5 Dell - ATX
> power adapter that is available.
>
> The main I dont want is to get smoke coming out of the machine!!!!!!!
Oh, THANK you for telling us this, the p3 and P2 dells are NOT atx. It
looks like atx, but it ain't. You may be stuck with the PSU you have
got, for now. Use the converter if you really have a pressing need for
the larger PSU, such as a bunch of HDDS, or something. But there's
enough margin in the dell psu to run 2 hdds, 2, cds, and a floppy.
> I have bad news guys and will proably get loads of grief for it. Its
> an old Dell!!!!!!!!!!!, I have read bits and bobs that the -5V is
> probably only used for the ISA slot (not used by me or anyone I
> think!!!) and the onboard sound (Im guessing an old sound card
> installed on an empty PCI slot would overcome this?). Im just not in
> a position to buy a whole new setup and would rather just get a new
> ATX PSU (which I can then use in the future) and a $5 Dell - ATX
> power adapter that is available.
>
> The main I dont want is to get smoke coming out of the machine!!!!!!!
Dell is a high volume seller, so theyre not going to specify PSUs with
a feature they dont use. Therefore it needs the -5v.
I dont know why you need another psu though, yours faulty?
Finally you can upgrade psu capability wihout replacing te psu by
adding a small 5v or regulated 12v psu to run some drives, if its
really needed.
>> I have bad news guys and will proably get loads of grief for it. Its
>> an old Dell!!!!!!!!!!!, I have read bits and bobs that the -5V is
>> probably only used for the ISA slot (not used by me or anyone I
>> think!!!) and the onboard sound (Im guessing an old sound card
>> installed on an empty PCI slot would overcome this?). Im just not in
>> a position to buy a whole new setup and would rather just get a new
>> ATX PSU (which I can then use in the future) and a $5 Dell - ATX
>> power adapter that is available.
>> The main I dont want is to get smoke coming out of the machine!!!!!!!
> Dell is a high volume seller, so theyre not going to specify
> PSUs with a feature they dont use. Therefore it needs the -5v.
You cant assume that. Bet it doesnt use -5V, its not used for much at all.
> I dont know why you need another psu though, yours faulty?
> Finally you can upgrade psu capability wihout replacing te psu by
> adding a small 5v or regulated 12v psu to run some drives, if its
> really needed.
Rod Speed wrote:
> meow2222@care2.com wrote
> > Glendon wrote
>
> >> I have bad news guys and will proably get loads of grief for it. Its
> >> an old Dell!!!!!!!!!!!, I have read bits and bobs that the -5V is
> >> probably only used for the ISA slot (not used by me or anyone I
> >> think!!!) and the onboard sound (Im guessing an old sound card
> >> installed on an empty PCI slot would overcome this?). Im just not in
> >> a position to buy a whole new setup and would rather just get a new
> >> ATX PSU (which I can then use in the future) and a $5 Dell - ATX
> >> power adapter that is available.
>
> >> The main I dont want is to get smoke coming out of the machine!!!!!!!
>
> > Dell is a high volume seller, so theyre not going to specify
> > PSUs with a feature they dont use. Therefore it needs the -5v.
>
> You cant assume that. Bet it doesnt use -5V, its not used for much at all.
>
P3 and P2 dells have different pinouts. THAT's the problem.
>>>> I have bad news guys and will proably get loads of grief for it.
>>>> Its an old Dell!!!!!!!!!!!, I have read bits and bobs that the -5V
>>>> is probably only used for the ISA slot (not used by me or anyone I
>>>> think!!!) and the onboard sound (Im guessing an old sound card
>>>> installed on an empty PCI slot would overcome this?). Im just not
>>>> in a position to buy a whole new setup and would rather just get a
>>>> new ATX PSU (which I can then use in the future) and a $5 Dell -
>>>> ATX power adapter that is available.
>>>> The main I dont want is to get smoke coming out of the machine!!!!!!!
>>> Dell is a high volume seller, so theyre not going to specify
>>> PSUs with a feature they dont use. Therefore it needs the -5v.
>> You cant assume that. Bet it doesnt use -5V, its not used for much at all.
> P3 and P2 dells have different pinouts. THAT's the problem.
I wasnt talking about that, just the claim that there is only -5V
because its actually being used. I dont believe it is being used.
> You will note that dell puts 5v on pin 1, where Standard ATX uses
> 3.3V, among other changes. Also, Dell has that extra 6-pin connector.
> In short, WHETHER OR NOT Dell uses -5v. It's NOT compatable with ATX.
Not relevant for the OP, he had decided to use a standard power
supply with an adapter. He's just concerned about whether the
system will actually use -5V and so the adapter wont work since
there is no -5V rail on the supply he wants to use, with an adapter.
> > Dell is a high volume seller, so theyre not going to specify
> > PSUs with a feature they dont use. Therefore it needs the -5v.
>
> You cant assume that. Bet it doesnt use -5V, its not used for much at all.
I didnt assume it, fool. Logic and fact versus assumption.
> paulmd@efn.org wrote
>
>>Rod Speed wrote
>>
>>>meow2222@care2.com wrote
>>>
>>>>Glendon wrote
>
>
>>>>>I have bad news guys and will proably get loads of grief for it.
>>>>>Its an old Dell!!!!!!!!!!!, I have read bits and bobs that the -5V
>>>>>is probably only used for the ISA slot (not used by me or anyone I
>>>>>think!!!) and the onboard sound (Im guessing an old sound card
>>>>>installed on an empty PCI slot would overcome this?). Im just not
>>>>>in a position to buy a whole new setup and would rather just get a
>>>>>new ATX PSU (which I can then use in the future) and a $5 Dell -
>>>>>ATX power adapter that is available.
>
>
>>>>>The main I dont want is to get smoke coming out of the machine!!!!!!!
>
>
>>>>Dell is a high volume seller, so theyre not going to specify
>>>>PSUs with a feature they dont use. Therefore it needs the -5v.
>
>
>>>You cant assume that. Bet it doesnt use -5V, its not used for much at all.
>
>
>>P3 and P2 dells have different pinouts. THAT's the problem.
>
>
> We'll see...
>
>
>>THIS is Dell Special PSU
>>http://pinouts.ru/Power/dell_atxpower_pinout.shtml
>>http://pinouts.ru/Power/dell_atxaux_pinout.shtml
>
>
>>THIS is Standard ATX
>>http://pinouts.ru/Power/atxpower_pinout.shtml
>
>
> I wasnt talking about that, just the claim that there is only -5V
> because its actually being used. I dont believe it is being used.
>
>
>>You will note that dell puts 5v on pin 1, where Standard ATX uses
>>3.3V, among other changes. Also, Dell has that extra 6-pin connector.
>
>
>>In short, WHETHER OR NOT Dell uses -5v. It's NOT compatable with ATX.
>
>
> Not relevant for the OP, he had decided to use a standard power
> supply with an adapter. He's just concerned about whether the
> system will actually use -5V and so the adapter wont work since
> there is no -5V rail on the supply he wants to use, with an adapter.
>
>
>Glendon wrote:
>
>> I have bad news guys and will proably get loads of grief for it. Its
>> an old Dell!!!!!!!!!!!, I have read bits and bobs that the -5V is
>> probably only used for the ISA slot (not used by me or anyone I
>> think!!!) and the onboard sound (Im guessing an old sound card
>> installed on an empty PCI slot would overcome this?).
>>Im just not in
>> a position to buy a whole new setup and would rather just get a new
>> ATX PSU (which I can then use in the future) and a $5 Dell - ATX
>> power adapter that is available.
>>
>> The main I dont want is to get smoke coming out of the machine!!!!!!!
>
>Dell is a high volume seller, so theyre not going to specify PSUs with
>a feature they dont use. Therefore it needs the -5v.
No.
Dell does not sell only one type of system, they're not
going to have custom PSUs built for every possible
configuration. It could easily be that any given system
with a PSU supporting -5V, does not actually use that -5V.
>
>I dont know why you need another psu though, yours faulty?
>
>Finally you can upgrade psu capability wihout replacing te psu by
>adding a small 5v or regulated 12v psu to run some drives, if its
>really needed.
While that's possible (providing a common ground is used),
such dedicated supplies tend to cost quite as much if not
more than commodity grade ATX, even if one has to buy a Dell
adapter for it. Also, Dell had used some pretty high
quality PSU in that era, certainly enough to support adding
a drive or two... so if there were other addt'l upgrades
enough to exceed the current capability of the PSU, taking
away on the amount of current for a couple drives (which
after initial turn-on, should only be about an amp per rail)
is still quite low margin, compared to buying a typical 420W
PSU which can now be had for about $30 AR (for example
Thermaltake 420W @ newegg.com).
>Rod Speed wrote:
>> meow2222@care2.com wrote
>
>> > Dell is a high volume seller, so theyre not going to specify
>> > PSUs with a feature they dont use. Therefore it needs the -5v.
>>
>> You cant assume that. Bet it doesnt use -5V, its not used for much at all.
>
>I didnt assume it, fool. Logic and fact versus assumption.
Actually no, there is no basis for the presumption that a
typical Dell P2 or P3 era system uses -5V for anything.
Dell would have to also be using actual components that
needed -5V, for starters...
"Merrill P. L. Worthington" wrote:
>
> Don't pay attention to Rod Speed, the troll.
Will you please stop quoting his trolls in their entirety. This
serves only to impinge on those of us who have him plonked. If you
want to point out his trolling, it takes only the one line I have
quoted above. Better yet, plonk and ignore him.
--
"I'm the commander--see, I don't have to explain -- I don't need
to explain why I say things. That's the interesting thing about
being the President. Maybe somebody needs to explain to me why
they say something, but I don't feel like I owe anybody an
explanation." - George W. Bush, 2002-11-19
> >Dell is a high volume seller, so theyre not going to specify PSUs with
> >a feature they dont use. Therefore it needs the -5v.
> No.
>
> Dell does not sell only one type of system, they're not
> going to have custom PSUs built for every possible
> configuration. It could easily be that any given system
> with a PSU supporting -5V, does not actually use that -5V.
For low volume production, using a limited range of psus makes sense.
But when you're selling a milion of a model, using a psu tailored to
each model saves a company a fortune. And you'd be hard pressed to find
a major company unwise to such business basics. For example, say we
could save 40c by leaving out the -5 rail on a million machines...
thats $400,000. No-one thorws that much away and stays in business.
> While that's possible (providing a common ground is used),
> such dedicated supplies tend to cost quite as much if not
> more than commodity grade ATX, even if one has to buy a Dell
> adapter for it.
probably. OTOH many people will have a stabilised 12v wallwart lying
around. But I'd agree the need is not that likely.
>kony wrote:
>> On 4 Sep 2006 17:56:04 -0700, meow2222@care2.com wrote:
>
>> >Dell is a high volume seller, so theyre not going to specify PSUs with
>> >a feature they dont use. Therefore it needs the -5v.
>
>> No.
>>
>> Dell does not sell only one type of system, they're not
>> going to have custom PSUs built for every possible
>> configuration. It could easily be that any given system
>> with a PSU supporting -5V, does not actually use that -5V.
>
>For low volume production, using a limited range of psus makes sense.
>But when you're selling a milion of a model, using a psu tailored to
>each model saves a company a fortune. And you'd be hard pressed to find
>a major company unwise to such business basics. For example, say we
>could save 40c by leaving out the -5 rail on a million machines...
>thats $400,000. No-one thorws that much away and stays in business.
Untrue, it could actually cost more to omit that part if the
PSU manufacturer (which is not Dell) were already producing
the whole board for many uses instead of setting up a
separate line or entirely new design, and Dell only needed a
different wiring harness on it for their proprietary pinout
(which was the case, I have actually modified one of those
Dell PSU to power a standard ATX board).
>>> Dell is a high volume seller, so theyre not going to specify
>>> PSUs with a feature they dont use. Therefore it needs the -5v.
>> No.
>> Dell does not sell only one type of system, they're not
>> going to have custom PSUs built for every possible
>> configuration. It could easily be that any given system
>> with a PSU supporting -5V, does not actually use that -5V.
> For low volume production, using a limited range of psus
> makes sense. But when you're selling a milion of a model,
> using a psu tailored to each model saves a company a fortune.
Fantasy with dropping the -5V rail. That would save them bugger all.
> And you'd be hard pressed to find a major
> company unwise to such business basics.
Have fun explaining how come even
Dell NOW uses standard power supplys.
> For example, say we could save 40c by leaving out the -5 rail on a million
> machines...
Dell doesnt move a million machines.
> thats $400,000. No-one thorws that much away and stays in business.
Have fun explaining how come even
Dell NOW uses standard power supplys.
> >> >Dell is a high volume seller, so theyre not going to specify PSUs with
> >> >a feature they dont use. Therefore it needs the -5v.
> >> No.
> >>
> >> Dell does not sell only one type of system, they're not
> >> going to have custom PSUs built for every possible
> >> configuration. It could easily be that any given system
> >> with a PSU supporting -5V, does not actually use that -5V.
> >For low volume production, using a limited range of psus makes sense.
> >But when you're selling a milion of a model, using a psu tailored to
> >each model saves a company a fortune. And you'd be hard pressed to find
> >a major company unwise to such business basics. For example, say we
> >could save 40c by leaving out the -5 rail on a million machines...
> >thats $400,000. No-one thorws that much away and stays in business.
> Untrue, it could actually cost more to omit that part if the
> PSU manufacturer (which is not Dell) were already producing
> the whole board for many uses instead of setting up a
> separate line or entirely new design,
Thats not what I was suggesting at all. The normal thing is to make the
same psu or whatever item it is, but leave out any components not
needed for that model. This is standard practice in volume production.
>kony wrote:
>> On 5 Sep 2006 18:09:38 -0700, meow2222@care2.com wrote:
>> >kony wrote:
>> >> On 4 Sep 2006 17:56:04 -0700, meow2222@care2.com wrote:
>
>> >> >Dell is a high volume seller, so theyre not going to specify PSUs with
>> >> >a feature they dont use. Therefore it needs the -5v.
>
>> >> No.
>> >>
>> >> Dell does not sell only one type of system, they're not
>> >> going to have custom PSUs built for every possible
>> >> configuration. It could easily be that any given system
>> >> with a PSU supporting -5V, does not actually use that -5V.
>
>> >For low volume production, using a limited range of psus makes sense.
>> >But when you're selling a milion of a model, using a psu tailored to
>> >each model saves a company a fortune. And you'd be hard pressed to find
>> >a major company unwise to such business basics. For example, say we
>> >could save 40c by leaving out the -5 rail on a million machines...
>> >thats $400,000. No-one thorws that much away and stays in business.
>
>> Untrue, it could actually cost more to omit that part if the
>> PSU manufacturer (which is not Dell) were already producing
>> the whole board for many uses instead of setting up a
>> separate line or entirely new design,
>
>Thats not what I was suggesting at all. The normal thing is to make the
>same psu or whatever item it is, but leave out any components not
>needed for that model. This is standard practice in volume production.
Again, leaving out the components means changing the line,
which can easily be more expensive than a couple of part
that are of trivial cost (pennies at most). Just having the
line, off-line long enough to do the switch would be a
greater loss (and expense) than that.
meow2222@care2.com wrote:
> kony wrote:
>> On 5 Sep 2006 18:09:38 -0700, meow2222@care2.com wrote:
>>> kony wrote:
>>>> On 4 Sep 2006 17:56:04 -0700, meow2222@care2.com wrote:
>
>>>>> Dell is a high volume seller, so theyre not going to specify PSUs
>>>>> with a feature they dont use. Therefore it needs the -5v.
>
>>>> No.
>>>>
>>>> Dell does not sell only one type of system, they're not
>>>> going to have custom PSUs built for every possible
>>>> configuration. It could easily be that any given system
>>>> with a PSU supporting -5V, does not actually use that -5V.
>
>>> For low volume production, using a limited range of psus makes
>>> sense. But when you're selling a milion of a model, using a psu
>>> tailored to each model saves a company a fortune. And you'd be hard
>>> pressed to find a major company unwise to such business basics. For
>>> example, say we could save 40c by leaving out the -5 rail on a
>>> million machines... thats $400,000. No-one thorws that much away
>>> and stays in business.
>
>> Untrue, it could actually cost more to omit that part if the
>> PSU manufacturer (which is not Dell) were already producing
>> the whole board for many uses instead of setting up a
>> separate line or entirely new design,
>
> Thats not what I was suggesting at all. The normal thing is to make
> the same psu or whatever item it is, but leave out any components not
> needed for that model. This is standard practice in volume production.
Have fun explaining how come Dell didnt drop the -5V
rail when they started to use standard ATX supplys.
Rod Speed wrote:
> meow2222@care2.com wrote:
>
>>kony wrote:
>>
>>>On 5 Sep 2006 18:09:38 -0700, meow2222@care2.com wrote:
>>>
>>>>kony wrote:
>>>>
>>>>>On 4 Sep 2006 17:56:04 -0700, meow2222@care2.com wrote:
>>
>>>>>>Dell is a high volume seller, so theyre not going to specify PSUs
>>>>>>with a feature they dont use. Therefore it needs the -5v.
>>
>>>>>No.
>>>>>
>>>>>Dell does not sell only one type of system, they're not
>>>>>going to have custom PSUs built for every possible
>>>>>configuration. It could easily be that any given system
>>>>>with a PSU supporting -5V, does not actually use that -5V.
>>
>>>>For low volume production, using a limited range of psus makes
>>>>sense. But when you're selling a milion of a model, using a psu
>>>>tailored to each model saves a company a fortune. And you'd be hard
>>>>pressed to find a major company unwise to such business basics. For
>>>>example, say we could save 40c by leaving out the -5 rail on a
>>>>million machines... thats $400,000. No-one thorws that much away
>>>>and stays in business.
>>
>>>Untrue, it could actually cost more to omit that part if the
>>>PSU manufacturer (which is not Dell) were already producing
>>>the whole board for many uses instead of setting up a
>>>separate line or entirely new design,
>>
>>Thats not what I was suggesting at all. The normal thing is to make
>>the same psu or whatever item it is, but leave out any components not
>>needed for that model. This is standard practice in volume production.
>
>
> Have fun explaining how come Dell didnt drop the -5V
> rail when they started to use standard ATX supplys.
>
>
Because they had very bad publicity over
their propriatry supplies??
>>>>>>> Dell is a high volume seller, so theyre not going to specify
>>>>>>> PSUs with a feature they dont use. Therefore it needs the -5v.
>>>>>> No.
>>>>>> Dell does not sell only one type of system, they're not
>>>>>> going to have custom PSUs built for every possible
>>>>>> configuration. It could easily be that any given system
>>>>>> with a PSU supporting -5V, does not actually use that -5V.
>>>>> For low volume production, using a limited range of psus makes
>>>>> sense. But when you're selling a milion of a model, using a psu
>>>>> tailored to each model saves a company a fortune. And you'd be
>>>>> hard pressed to find a major company unwise to such business
>>>>> basics. For example, say we could save 40c by leaving out the -5
>>>>> rail on a million machines... thats $400,000. No-one thorws that
>>>>> much away and stays in business.
>>>> Untrue, it could actually cost more to omit that part if the
>>>> PSU manufacturer (which is not Dell) were already producing
>>>> the whole board for many uses instead of setting up a
>>>> separate line or entirely new design,
>>> Thats not what I was suggesting at all. The normal thing is to make
>>> the same psu or whatever item it is, but leave out any components not needed
>>> for that model. This is standard practice in volume production.
>> Have fun explaining how come Dell didnt drop the -5V
>> rail when they started to use standard ATX supplys.
> Because they had very bad publicity over their propriatry supplies??
Not relevant. If they had supplied the original supply with the
components for the -5V rail missing, someone replacing that
supply when it failed could use a standard ATX supply which
has the -5V rail components included without any problem.
> >> >> >Dell is a high volume seller, so theyre not going to specify PSUs with
> >> >> >a feature they dont use. Therefore it needs the -5v.
> >
> >> >> No.
> >> >>
> >> >> Dell does not sell only one type of system, they're not
> >> >> going to have custom PSUs built for every possible
> >> >> configuration. It could easily be that any given system
> >> >> with a PSU supporting -5V, does not actually use that -5V.
> >
> >> >For low volume production, using a limited range of psus makes sense.
> >> >But when you're selling a milion of a model, using a psu tailored to
> >> >each model saves a company a fortune. And you'd be hard pressed to find
> >> >a major company unwise to such business basics. For example, say we
> >> >could save 40c by leaving out the -5 rail on a million machines...
> >> >thats $400,000. No-one thorws that much away and stays in business.
> >
> >> Untrue, it could actually cost more to omit that part if the
> >> PSU manufacturer (which is not Dell) were already producing
> >> the whole board for many uses instead of setting up a
> >> separate line or entirely new design,
> >
> >Thats not what I was suggesting at all. The normal thing is to make the
> >same psu or whatever item it is, but leave out any components not
> >needed for that model. This is standard practice in volume production.
>
> Again, leaving out the components means changing the line,
> which can easily be more expensive than a couple of part
> that are of trivial cost (pennies at most). Just having the
> line, off-line long enough to do the switch would be a
> greater loss (and expense) than that.
1,000,000 pcs @ 20c each is $20,000. I've only worked with small scale
assembly plant, not large, but I'd be surprised if stuffing machines
needed to be stopped for more than a minute if at all, to give them new
instructions. Nothing else need stop.
>> Again, leaving out the components means changing the line,
>> which can easily be more expensive than a couple of part
>> that are of trivial cost (pennies at most). Just having the
>> line, off-line long enough to do the switch would be a
>> greater loss (and expense) than that.
>
>1,000,000 pcs @ 20c each is $20,000.
#1, it wouldn't cost 20c
#2, they didn't make remotely near 1,000,000 of them, think
closer to zero.
>I've only worked with small scale
>assembly plant, not large, but I'd be surprised if stuffing machines
>needed to be stopped for more than a minute if at all, to give them new
>instructions. Nothing else need stop.
Apparently it's not so with larger production, plenty of
times you see open examples of it, for example unused
functions on PCChips motherboards, and PCChips is not a
company that splurges on excess parts if they can reduce the
cost.
More to the point, you seem to be implying that Dell would
omit these -5V but nobody else would. It's not the case,
the systems themselves are the evidence of what they decided
(or though indecision, lack of action), to do.
meow2222@care2.com wrote:
> kony wrote:
>> On 6 Sep 2006 17:26:27 -0700, meow2222@care2.com wrote:
>>> kony wrote:
>>>> On 5 Sep 2006 18:09:38 -0700, meow2222@care2.com wrote:
>>>>> kony wrote:
>>>>>> On 4 Sep 2006 17:56:04 -0700, meow2222@care2.com wrote:
>
>>>>>>> Dell is a high volume seller, so theyre not going to specify
>>>>>>> PSUs with a feature they dont use. Therefore it needs the -5v.
>>>
>>>>>> No.
>>>>>>
>>>>>> Dell does not sell only one type of system, they're not
>>>>>> going to have custom PSUs built for every possible
>>>>>> configuration. It could easily be that any given system
>>>>>> with a PSU supporting -5V, does not actually use that -5V.
>>>
>>>>> For low volume production, using a limited range of psus makes
>>>>> sense. But when you're selling a milion of a model, using a psu
>>>>> tailored to each model saves a company a fortune. And you'd be
>>>>> hard pressed to find a major company unwise to such business
>>>>> basics. For example, say we could save 40c by leaving out the -5
>>>>> rail on a million machines... thats $400,000. No-one thorws that
>>>>> much away and stays in business.
>>>
>>>> Untrue, it could actually cost more to omit that part if the
>>>> PSU manufacturer (which is not Dell) were already producing
>>>> the whole board for many uses instead of setting up a
>>>> separate line or entirely new design,
>>>
>>> Thats not what I was suggesting at all. The normal thing is to make
>>> the same psu or whatever item it is, but leave out any components
>>> not needed for that model. This is standard practice in volume
>>> production.
>>
>> Again, leaving out the components means changing the line,
>> which can easily be more expensive than a couple of part
>> that are of trivial cost (pennies at most). Just having the
>> line, off-line long enough to do the switch would be a
>> greater loss (and expense) than that.
> 1,000,000 pcs @ 20c each is $20,000.
Pity that ignores the cost of specials.
> I've only worked with small scale assembly plant, not large,
Thats obvious.
And you clearly dont have a clue about
real costs for an operation like Dell either.
> but I'd be surprised if stuffing machines needed
> to be stopped for more than a minute if at all, to
> give them new instructions. Nothing else need stop.
PSU question - confused 
Linear Mode
