I have an Inspiron 1545 that suffering an odd video problem:
1) On startup (pre-desktop) the screen can be very jittery, but the
color is mostly good.
2) After the desktop appears, it is filled with patches of wavy
static--it looks like that for *some* colors, the palette is constantly
shifting. Other parts of the screen appear to be stable.
3) Opening a window on the desktop produces a mostly stable image,
although some portions of the new window will have that same wavy
static. It looks like photos are more susceptible to the static than
solid colored backgrounds with text.
4) Booting from a Linux boot livecd produces the same output as
described above.
5) Hooking up an external monitor produces good clean video.
So, I'm include to conclude:
a) It's a hardware problem.
b) More specifically, in either the flat panel, or the inverter.
Does anyone care to hazard a more specific guess as to what component is
bad? I can get the whole top half of the laptop off of eBay for about
$120, but would prefer to replace a $20 inverter if that's the likely
culprit.
Grinder wrote:
> I have an Inspiron 1545 that suffering an odd video problem:
>
> 1) On startup (pre-desktop) the screen can be very jittery, but the
> color is mostly good.
>
> 2) After the desktop appears, it is filled with patches of wavy
> static--it looks like that for *some* colors, the palette is constantly
> shifting. Other parts of the screen appear to be stable.
>
> 3) Opening a window on the desktop produces a mostly stable image,
> although some portions of the new window will have that same wavy
> static. It looks like photos are more susceptible to the static than
> solid colored backgrounds with text.
>
> 4) Booting from a Linux boot livecd produces the same output as
> described above.
>
> 5) Hooking up an external monitor produces good clean video.
>
> So, I'm include to conclude:
>
> a) It's a hardware problem.
>
> b) More specifically, in either the flat panel, or the inverter.
>
> Does anyone care to hazard a more specific guess as to what component is
> bad? I can get the whole top half of the laptop off of eBay for about
> $120, but would prefer to replace a $20 inverter if that's the likely
> culprit.
>
> Thanks for your consideration.
So your thinking is, it's an electrical interference problem ?
The wavy static, suggests transmission errors. Maybe the cable
is routed near something it shouldn't be next to ?
I suppose it could also be related to how the panel is powered,
but then, why doesn't the panel just "go insane" if that was
the case ? It sounds more like an interference problem.
> I have an Inspiron 1545 that suffering an odd video problem:
>
> 1) On startup (pre-desktop) the screen can be very jittery, but the
> color is mostly good.
>
> 2) After the desktop appears, it is filled with patches of wavy
> static--it looks like that for *some* colors, the palette is constantly
> shifting. Other parts of the screen appear to be stable.
>
> 3) Opening a window on the desktop produces a mostly stable image,
> although some portions of the new window will have that same wavy
> static. It looks like photos are more susceptible to the static than
> solid colored backgrounds with text.
>
> 4) Booting from a Linux boot livecd produces the same output as
> described above.
>
> 5) Hooking up an external monitor produces good clean video.
>
> So, I'm include to conclude:
>
> a) It's a hardware problem.
>
> b) More specifically, in either the flat panel, or the inverter.
>
> Does anyone care to hazard a more specific guess as to what component is
> bad? I can get the whole top half of the laptop off of eBay for about
> $120, but would prefer to replace a $20 inverter if that's the likely
> culprit.
>
> Thanks for your consideration.
It it were the inverter, you would have problems lighting up the cold
cathode tubes that require high voltage to produce light. Instead of
seeing jitter or blotches on the screen, you would see a black screen
(if all tubes were unlit) or lighting only from some sides. Since the
inverter is part of the PCB attached to the LCD panel and they come as
an assembly, you'll end up replacing the whole LCD panel assembly (with
inverter and CCFLs) or figuring out how to find the parts and trying to
dismantle the thing to repair yourself (they make kits for this since
dismantling can destroy some parts). If you have to replace the
inverter, you might as well as replace the CCFLs, too, since as they age
they can require a greater draw from the inverter which is why the
inverter burned out. If you just replace the inverter, it could blow
out after a short time because you still have the higher drawing CCFLs.
Once you include the inverter, CCFLs (cost depends on how many and
quality in color temperature and lumens output), and a repair kit
(~$25), you'll probably be up to around $80-90. It would probably be
much easier to just replace the display panel assembly rather than try
to repair it (which is an iffy situation since you're taking about the
metal chassis for the assembly, removing the diffuser to get at the
CCFLs, having to do some soldering to replace the CCFLs, and then hope
you get it all aligned on reassembly). Plus the assembled LCD panel
might include a warranty whereas you could spend all that money and end
up with a worse panel than with what you started.
Doesn't look like its an inverter problem since you make no mention of
uneven lighting or a black screen. If you twist the LCD panel (just put
light pressure on the edges in opposite directions, don't try bending
it) or you press your finger onto the LCD panel while moving it around,
do the symptoms change while you twist? Is the "wavy" appearance
somewhat static in its position on the screen or is it moving around?
Could be the screen panel got severely torqued. It is, after all, a
*liquid* crystal display and severe twisting. If you've ever hammered a
LCD panel, you'd see the bleeding along the cracks. Slightly twisting
the LCD panel or apply pressure with your finger should produce some
wavy effect, like a ring pattern that follows your finger. However, if
you move your finger firmly across the wavy areas and they don't change
then there has been permanent damage to the LCD panel, like it got
dropped, sat on, overly twisted, punched, or otherwise abused.
Since you mention an *external* monitor works okay, and because I'm not
going to bother looking up the specs on the brand and model simply
because the info was omitted, I'm guessing you're talking about a
laptop. So who has been using it besides yourself? Have the kids been
knocking it around? Did you sit on it?
On 12/30/2011 2:08 PM, Grinder wrote:
> I have an Inspiron 1545 that suffering an odd video problem:
>
> 1) On startup (pre-desktop) the screen can be very jittery, but the
> color is mostly good.
>
> 2) After the desktop appears, it is filled with patches of wavy
> static--it looks like that for *some* colors, the palette is constantly
> shifting. Other parts of the screen appear to be stable.
>
> 3) Opening a window on the desktop produces a mostly stable image,
> although some portions of the new window will have that same wavy
> static. It looks like photos are more susceptible to the static than
> solid colored backgrounds with text.
>
> 4) Booting from a Linux boot livecd produces the same output as
> described above.
>
> 5) Hooking up an external monitor produces good clean video.
>
> So, I'm include to conclude:
>
> a) It's a hardware problem.
>
> b) More specifically, in either the flat panel, or the inverter.
>
> Does anyone care to hazard a more specific guess as to what component is
> bad? I can get the whole top half of the laptop off of eBay for about
> $120, but would prefer to replace a $20 inverter if that's the likely
> culprit.
>
> Thanks for your consideration.
Like others have said, the inverter is not the problem based on the
symptoms. It could be something as simple as the ribbon cable from the
display needing to be reseated where it plugs into the motherboard.
It could actually be loose at either end of the ribbon cable but I'd
start with the easiest end to work on.
Using one of the many "how to do it" guides for replacing a screen would
help. You may even find a YouTube video showing how to take things
apart and do it.
Remote since the problem persists between Windows and a Live Linux boot
but try reseating/swapping the memory module(s) first since many video
systems share memory with the motherboard, but I suspect the problem
will be with either the ribbon cable or the actual video driver
circuitry feeding the internal display.
On 12/30/2011 3:08 PM, Grinder wrote:
> I have an Inspiron 1545 that suffering an odd video problem:
>
> 1) On startup (pre-desktop) the screen can be very jittery,
> but the color is mostly good.
>
> 2) After the desktop appears, it is filled with patches of
> wavy static--it looks like that for *some* colors, the
> palette is constantly shifting. Other parts of the screen
> appear to be stable.
>
> 3) Opening a window on the desktop produces a mostly stable
> image, although some portions of the new window will have
> that same wavy static. It looks like photos are more
> susceptible to the static than solid colored backgrounds
> with text.
>
> 4) Booting from a Linux boot livecd produces the same output
> as described above.
>
> 5) Hooking up an external monitor produces good clean video.
>
> So, I'm include to conclude:
>
> a) It's a hardware problem.
>
> b) More specifically, in either the flat panel, or the
> inverter.
>
> Does anyone care to hazard a more specific guess as to what
> component is bad? I can get the whole top half of the
> laptop off of eBay for about $120, but would prefer to
> replace a $20 inverter if that's the likely culprit.
>
> Thanks for your consideration.
If you wish to try the suggestions made here to check and
re-seat the cables then go here and download the Dell
Service manual
On 12/30/2011 3:28 PM, VanguardLH wrote:
> Grinder wrote:
>
>> I have an Inspiron 1545 that suffering an odd video problem:
>>
>> 1) On startup (pre-desktop) the screen can be very jittery, but the
>> color is mostly good.
>>
>> 2) After the desktop appears, it is filled with patches of wavy
>> static--it looks like that for *some* colors, the palette is constantly
>> shifting. Other parts of the screen appear to be stable.
>>
>> 3) Opening a window on the desktop produces a mostly stable image,
>> although some portions of the new window will have that same wavy
>> static. It looks like photos are more susceptible to the static than
>> solid colored backgrounds with text.
>>
>> 4) Booting from a Linux boot livecd produces the same output as
>> described above.
>>
>> 5) Hooking up an external monitor produces good clean video.
>>
>> So, I'm include to conclude:
>>
>> a) It's a hardware problem.
>>
>> b) More specifically, in either the flat panel, or the inverter.
>>
>> Does anyone care to hazard a more specific guess as to what component is
>> bad? I can get the whole top half of the laptop off of eBay for about
>> $120, but would prefer to replace a $20 inverter if that's the likely
>> culprit.
>>
>> Thanks for your consideration.
>
> It it were the inverter, you would have problems lighting up the cold
> cathode tubes that require high voltage to produce light. Instead of
> seeing jitter or blotches on the screen, you would see a black screen
> (if all tubes were unlit) or lighting only from some sides. Since the
> inverter is part of the PCB attached to the LCD panel and they come as
> an assembly, you'll end up replacing the whole LCD panel assembly (with
> inverter and CCFLs) or figuring out how to find the parts and trying to
> dismantle the thing to repair yourself (they make kits for this since
> dismantling can destroy some parts). If you have to replace the
> inverter, you might as well as replace the CCFLs, too, since as they age
> they can require a greater draw from the inverter which is why the
> inverter burned out. If you just replace the inverter, it could blow
> out after a short time because you still have the higher drawing CCFLs.
> Once you include the inverter, CCFLs (cost depends on how many and
> quality in color temperature and lumens output), and a repair kit
> (~$25), you'll probably be up to around $80-90. It would probably be
> much easier to just replace the display panel assembly rather than try
> to repair it (which is an iffy situation since you're taking about the
> metal chassis for the assembly, removing the diffuser to get at the
> CCFLs, having to do some soldering to replace the CCFLs, and then hope
> you get it all aligned on reassembly). Plus the assembled LCD panel
> might include a warranty whereas you could spend all that money and end
> up with a worse panel than with what you started.
>
> Doesn't look like its an inverter problem since you make no mention of
> uneven lighting or a black screen. If you twist the LCD panel (just put
> light pressure on the edges in opposite directions, don't try bending
> it) or you press your finger onto the LCD panel while moving it around,
> do the symptoms change while you twist?
I'll try this, but my inclination is to say no. I had manipulated the
screen with no change in affect, but not in the specific way you suggest.
> Is the "wavy" appearance
> somewhat static in its position on the screen or is it moving around?
The regions that are affected are static, depending on the image
displayed, but within those regions, the colors are cycling through
various colors in a wavelike pattern.
> Could be the screen panel got severely torqued. It is, after all, a
> *liquid* crystal display and severe twisting. If you've ever hammered a
> LCD panel, you'd see the bleeding along the cracks. Slightly twisting
> the LCD panel or apply pressure with your finger should produce some
> wavy effect, like a ring pattern that follows your finger. However, if
> you move your finger firmly across the wavy areas and they don't change
> then there has been permanent damage to the LCD panel, like it got
> dropped, sat on, overly twisted, punched, or otherwise abused.
The affected areas appear to be determined by the image that is being
displayed. If I have a high color nature photograph, for instance,
there will be a lot of the screen's area that is screwed up. If it's a
solid color window with text, only a small portion of the window, in the
more colorful area will be affected.
> Since you mention an *external* monitor works okay, and because I'm not
> going to bother looking up the specs on the brand and model simply
> because the info was omitted, I'm guessing you're talking about a
> laptop. So who has been using it besides yourself? Have the kids been
> knocking it around?
An 83-year-old woman, possibly from Pasadena, has be the sole user of
this laptop. There are no signs of any physical damage.
On 12/30/2011 2:37 PM, Paul wrote:
> Grinder wrote:
>> I have an Inspiron 1545 that suffering an odd video problem:
>>
>> 1) On startup (pre-desktop) the screen can be very jittery, but the
>> color is mostly good.
>>
>> 2) After the desktop appears, it is filled with patches of wavy
>> static--it looks like that for *some* colors, the palette is
>> constantly shifting. Other parts of the screen appear to be stable.
>>
>> 3) Opening a window on the desktop produces a mostly stable image,
>> although some portions of the new window will have that same wavy
>> static. It looks like photos are more susceptible to the static than
>> solid colored backgrounds with text.
>>
>> 4) Booting from a Linux boot livecd produces the same output as
>> described above.
>>
>> 5) Hooking up an external monitor produces good clean video.
>>
>> So, I'm include to conclude:
>>
>> a) It's a hardware problem.
>>
>> b) More specifically, in either the flat panel, or the inverter.
>>
>> Does anyone care to hazard a more specific guess as to what component
>> is bad? I can get the whole top half of the laptop off of eBay for
>> about $120, but would prefer to replace a $20 inverter if that's the
>> likely culprit.
>>
>> Thanks for your consideration.
>
> So your thinking is, it's an electrical interference problem ?
I had not really thought of that. It's a laptop--sorry for not being
more explicit on that point--that suddenly presented this problem with
no discernible change in environment.
> The wavy static, suggests transmission errors. Maybe the cable
> is routed near something it shouldn't be next to ?
Given that it is a laptop that had previously be working fine in this
location, that seems unlikely. I supposed the cabling that sneaks
through the hinge could have been bound up in some way, and finally worn
through the insulator enough to cause problems?
> I suppose it could also be related to how the panel is powered,
> but then, why doesn't the panel just "go insane" if that was
> the case ? It sounds more like an interference problem.
I'll try to put up a picture of the screen so you can see what I mean.
On 12/30/2011 5:42 PM, GlowingBlueMist wrote:
> On 12/30/2011 2:08 PM, Grinder wrote:
>> I have an Inspiron 1545 that suffering an odd video problem:
>>
>> 1) On startup (pre-desktop) the screen can be very jittery, but the
>> color is mostly good.
>>
>> 2) After the desktop appears, it is filled with patches of wavy
>> static--it looks like that for *some* colors, the palette is constantly
>> shifting. Other parts of the screen appear to be stable.
>>
>> 3) Opening a window on the desktop produces a mostly stable image,
>> although some portions of the new window will have that same wavy
>> static. It looks like photos are more susceptible to the static than
>> solid colored backgrounds with text.
>>
>> 4) Booting from a Linux boot livecd produces the same output as
>> described above.
>>
>> 5) Hooking up an external monitor produces good clean video.
>>
>> So, I'm include to conclude:
>>
>> a) It's a hardware problem.
>>
>> b) More specifically, in either the flat panel, or the inverter.
>>
>> Does anyone care to hazard a more specific guess as to what component is
>> bad? I can get the whole top half of the laptop off of eBay for about
>> $120, but would prefer to replace a $20 inverter if that's the likely
>> culprit.
>>
>> Thanks for your consideration.
>
> Like others have said, the inverter is not the problem based on the
> symptoms. It could be something as simple as the ribbon cable from the
> display needing to be reseated where it plugs into the motherboard.
>
> It could actually be loose at either end of the ribbon cable but I'd
> start with the easiest end to work on.
>
> Using one of the many "how to do it" guides for replacing a screen would
> help. You may even find a YouTube video showing how to take things apart
> and do it.
>
> Remote since the problem persists between Windows and a Live Linux boot
> but try reseating/swapping the memory module(s) first since many video
> systems share memory with the motherboard, but I suspect the problem
> will be with either the ribbon cable or the actual video driver
> circuitry feeding the internal display.
I did try reseating the memory, but I have not run any tests, which I
probably should. The video display is pretty curious the way it only
seems to affect certain colors.
On 12/30/2011 5:51 PM, Pen wrote:
> On 12/30/2011 3:08 PM, Grinder wrote:
>> I have an Inspiron 1545 that suffering an odd video problem:
>>
>> 1) On startup (pre-desktop) the screen can be very jittery,
>> but the color is mostly good.
>>
>> 2) After the desktop appears, it is filled with patches of
>> wavy static--it looks like that for *some* colors, the
>> palette is constantly shifting. Other parts of the screen
>> appear to be stable.
>>
>> 3) Opening a window on the desktop produces a mostly stable
>> image, although some portions of the new window will have
>> that same wavy static. It looks like photos are more
>> susceptible to the static than solid colored backgrounds
>> with text.
>>
>> 4) Booting from a Linux boot livecd produces the same output
>> as described above.
>>
>> 5) Hooking up an external monitor produces good clean video.
>>
>> So, I'm include to conclude:
>>
>> a) It's a hardware problem.
>>
>> b) More specifically, in either the flat panel, or the
>> inverter.
>>
>> Does anyone care to hazard a more specific guess as to what
>> component is bad? I can get the whole top half of the
>> laptop off of eBay for about $120, but would prefer to
>> replace a $20 inverter if that's the likely culprit.
>>
>> Thanks for your consideration.
> If you wish to try the suggestions made here to check and
> re-seat the cables then go here and download the Dell
> Service manual
>
> http://support.dell.com/support/edoc...5/en/index.htm
Are you using the VGA or a digital connection to the monitor? Which of
its inputs are you using?
If VGA, and since that input is analog, the LCD monitor (just like for a
CRT monitor) may require calibration to get it to sync to the frequency
and sizing produced by the video output from the computer. You should
be using the native resolution of the LCD monitor. Anything else
requires both interpolation by the monitor along with needed calibration
to ensure it is using the correct sync frequency for the sizing needed
to get the image to paint to the edges of the monitor. It can be a pain
to get the calibration just right when using non-native sized
resolutions in the OS and why it's suggested to always use a screen
resolution that matches the native resolution of the monitor.
If the LCD monitor has an "Auto [adjust]" setting in its own config
menus to self-calibrate for aliasing (moire effect), try the following:
1. Browse to the following web site: http://www.tenpastmidnight.com/pc_ad...or_adjust.html
2. Maximise your web browser to fill the entire screen. Better yet is
to make the web browser's window full size (in IE, hit the F11 key to
toggle between fullscreen and windowed).
3. Use the 'Auto' or 'Adjust' button on your LCD monitor or find the
option in it's own menu.
Make sure you are running the screen resolution so it is the SAME as the
"native" resolution of your LCD monitor. If your LCD monitor is rated
for a native resolution (usually the highest resolution they specify) of
1900x1024 then set the OS screen resolution 1900x1024 and nothing else,
like 1900x1480, 1024x768, or anything else. Have the screen resolution
match the native resolution of the monitor; otherwise, you'll get video
artifacts from the required pixel-to-resolution interpolation, like loss
of sharpness (fuzziness), color tinging, and aliasing (moire) effects.
When screen resolution equals pixel resolution, there is no
interpolation.
For some folks, especially older folks, going up in resolution results
in smaller sized text that is harder to read. To make text sharper and
with more contrast requires they be painted using more pixels. Think of
like swiping a paint brush across a canvass: if you swipe fast and only
use a little paint then anything you write on the canvass will be harder
to read than if you use more paint to darken the text to give it more
contrast. Also, if you paint the text using the same number of dots but
stand farther away then the text is harder to read. Upping the DPI will
increase both the number of pixels used to paint the text while
increasing the size (to counteract the text getting smaller at higher
resolution). Anyone that buys a monitor to increase the maximum
resolution without also upping the DPI is throwing away their money to
get the higher resolution. Higher resolution without actually *using*
it to paint text using more pixels means you haven't increased the
resolution of the text at all. Instead you end up with the same
resolution for the text but with it also getting painted at a smaller
size. So make sure you are using a screen resolution in the OS that
matches the native resolution for the LCD monitor.
Check what output connectors are available from the backpanel of your
computer or the video card in your computer. Then check what
connections are available on the LCD monitor. If both have digital
connectors (DPMI or DVM) then use those; however, you'll need a
different cable to connect DPMI or DVM inputs and outputs since the
wiring is different as well as the connectors.
> On 12/31/2011 5:40 AM, VanguardLH wrote:
>> Are you using the VGA or a digital connection to the monitor? Which of
>> its inputs are you using?
>
> I was not very explicit to start--the machine in question is a laptop.
Which means all the suggestions about screen resolution matching
monitor's native resolution still applies.
I mentioned the DPI setting because making screen res = monitor res
often means having smaller text that is harder to read and resolution
has NOT improved for that text unless you up the DPI.
On 12/31/2011 11:22 AM, VanguardLH wrote:
> Grinder wrote:
>
>> On 12/31/2011 5:40 AM, VanguardLH wrote:
>>> Are you using the VGA or a digital connection to the monitor? Which of
>>> its inputs are you using?
>>
>> I was not very explicit to start--the machine in question is a laptop.
>
> Which means all the suggestions about screen resolution matching
> monitor's native resolution still applies.
>
> I mentioned the DPI setting because making screen res = monitor res
> often means having smaller text that is harder to read and resolution
> has NOT improved for that text unless you up the DPI.
Several resolutions have been tried, including native resolution, and it
has produced the same (aforementioned) effects. I'll put up a video of
it in a bit so that everyone can see what I've described.
On 12/30/2011 2:08 PM, Grinder wrote:
> I have an Inspiron 1545 that suffering an odd video problem:
>
> 1) On startup (pre-desktop) the screen can be very jittery, but the
> color is mostly good.
>
> 2) After the desktop appears, it is filled with patches of wavy
> static--it looks like that for *some* colors, the palette is constantly
> shifting. Other parts of the screen appear to be stable.
>
> 3) Opening a window on the desktop produces a mostly stable image,
> although some portions of the new window will have that same wavy
> static. It looks like photos are more susceptible to the static than
> solid colored backgrounds with text.
>
> 4) Booting from a Linux boot livecd produces the same output as
> described above.
>
> 5) Hooking up an external monitor produces good clean video.
>
> So, I'm include to conclude:
>
> a) It's a hardware problem.
>
> b) More specifically, in either the flat panel, or the inverter.
>
> Does anyone care to hazard a more specific guess as to what component is
> bad? I can get the whole top half of the laptop off of eBay for about
> $120, but would prefer to replace a $20 inverter if that's the likely
> culprit.
>
> Thanks for your consideration.
Re: Palette Shifting Craziness on Laptop Screen (Solved)
On 12/31/2011 5:09 PM, Grinder wrote:
> On 12/30/2011 2:08 PM, Grinder wrote:
>> I have an Inspiron 1545 that suffering an odd video problem:
>>
>> 1) On startup (pre-desktop) the screen can be very jittery, but the
>> color is mostly good.
>>
>> 2) After the desktop appears, it is filled with patches of wavy
>> static--it looks like that for *some* colors, the palette is constantly
>> shifting. Other parts of the screen appear to be stable.
>>
>> 3) Opening a window on the desktop produces a mostly stable image,
>> although some portions of the new window will have that same wavy
>> static. It looks like photos are more susceptible to the static than
>> solid colored backgrounds with text.
>>
>> 4) Booting from a Linux boot livecd produces the same output as
>> described above.
>>
>> 5) Hooking up an external monitor produces good clean video.
>>
>> So, I'm include to conclude:
>>
>> a) It's a hardware problem.
>>
>> b) More specifically, in either the flat panel, or the inverter.
>>
>> Does anyone care to hazard a more specific guess as to what component is
>> bad? I can get the whole top half of the laptop off of eBay for about
>> $120, but would prefer to replace a $20 inverter if that's the likely
>> culprit.
>>
>> Thanks for your consideration.
>
> Here's video of the laptop in question:
>
> http://youtu.be/73sKQ9jLTKo
>
> The effect seems to have gotten a bit worse since the last time I messed
> with it.
Problem solved. Apparently the motherboard connector that accepts the
cable from the flat panel is a bit screwy. It's taken a bit of
electrician's tape, but it seems to be working well now.
Thanks for all the speculation -- it was educational!
Grinder wrote:
> On 12/30/2011 2:08 PM, Grinder wrote:
>> I have an Inspiron 1545 that suffering an odd video problem:
>>
>> 1) On startup (pre-desktop) the screen can be very jittery, but the
>> color is mostly good.
>>
>> 2) After the desktop appears, it is filled with patches of wavy
>> static--it looks like that for *some* colors, the palette is constantly
>> shifting. Other parts of the screen appear to be stable.
>>
>> 3) Opening a window on the desktop produces a mostly stable image,
>> although some portions of the new window will have that same wavy
>> static. It looks like photos are more susceptible to the static than
>> solid colored backgrounds with text.
>>
>> 4) Booting from a Linux boot livecd produces the same output as
>> described above.
>>
>> 5) Hooking up an external monitor produces good clean video.
>>
>> So, I'm include to conclude:
>>
>> a) It's a hardware problem.
>>
>> b) More specifically, in either the flat panel, or the inverter.
>>
>> Does anyone care to hazard a more specific guess as to what component is
>> bad? I can get the whole top half of the laptop off of eBay for about
>> $120, but would prefer to replace a $20 inverter if that's the likely
>> culprit.
>>
>> Thanks for your consideration.
>
> Here's video of the laptop in question:
>
> http://youtu.be/73sKQ9jLTKo
>
> The effect seems to have gotten a bit worse since the last time I messed
> with it.
I had a look at the video.
It looks like of the RGB bits, R and G are affected, but B isn't. Perhaps
there is a problem with the R and G pairs on the ribbon cable to the panel.
The interface could consist of R+, R-, G+, G-, B+, B-, Clock+, Clock-.
Running at around 1650MHz (165MHz clock), you can move full screen video
at 60Hz frame rate. The panel then takes that pattern, and uses it to
drive row and column drivers. The clock rate is lower, as the panel
resolution gets lower.
The pixels are probably arranged in columns of colors. A column of R,
a column of G, a column of B. I can't imagine a defect down at the panel
level, that can account for the effect you're seeing.
Maybe the panel has an "input board" or function, but I doubt it. But
then, if it didn't, how does it handle resolution choices ? I looked
at my laptop, and some resolutions are supported by cropping. But
when I selected 800x600, that resulted in a magnified image (and not
by a factor of 2 either), which implies some re-sampling going on.
But even knowing that is a possibility, doesn't explain the noise pattern.
There'd be no process in the re-sampling, that would add noise like that.
The only thing I can think of at the moment, is one wire in the R+ R-
pair, one wire in the G+ G- pair, are open circuit. And the receiver
is no longer working on a solid, differential signal. Those signals
would be on the ribbon cable, between motherboard and panel (and
through the hinge).
On 12/31/2011 8:47 PM, Paul wrote:
> Grinder wrote:
>> On 12/30/2011 2:08 PM, Grinder wrote:
>>> I have an Inspiron 1545 that suffering an odd video problem:
>>>
>>> 1) On startup (pre-desktop) the screen can be very jittery, but the
>>> color is mostly good.
>>>
>>> 2) After the desktop appears, it is filled with patches of wavy
>>> static--it looks like that for *some* colors, the palette is constantly
>>> shifting. Other parts of the screen appear to be stable.
>>>
>>> 3) Opening a window on the desktop produces a mostly stable image,
>>> although some portions of the new window will have that same wavy
>>> static. It looks like photos are more susceptible to the static than
>>> solid colored backgrounds with text.
>>>
>>> 4) Booting from a Linux boot livecd produces the same output as
>>> described above.
>>>
>>> 5) Hooking up an external monitor produces good clean video.
>>>
>>> So, I'm include to conclude:
>>>
>>> a) It's a hardware problem.
>>>
>>> b) More specifically, in either the flat panel, or the inverter.
>>>
>>> Does anyone care to hazard a more specific guess as to what component is
>>> bad? I can get the whole top half of the laptop off of eBay for about
>>> $120, but would prefer to replace a $20 inverter if that's the likely
>>> culprit.
>>>
>>> Thanks for your consideration.
>>
>> Here's video of the laptop in question:
>>
>> http://youtu.be/73sKQ9jLTKo
>>
>> The effect seems to have gotten a bit worse since the last time I
>> messed with it.
>
> I had a look at the video.
>
> It looks like of the RGB bits, R and G are affected, but B isn't. Perhaps
> there is a problem with the R and G pairs on the ribbon cable to the panel.
>
> The interface could consist of R+, R-, G+, G-, B+, B-, Clock+, Clock-.
> Running at around 1650MHz (165MHz clock), you can move full screen video
> at 60Hz frame rate. The panel then takes that pattern, and uses it to
> drive row and column drivers. The clock rate is lower, as the panel
> resolution gets lower.
>
> The pixels are probably arranged in columns of colors. A column of R,
> a column of G, a column of B. I can't imagine a defect down at the panel
> level, that can account for the effect you're seeing.
>
> http://www.lagom.nl/lcd-test/subpixel.php
>
> Maybe the panel has an "input board" or function, but I doubt it. But
> then, if it didn't, how does it handle resolution choices ? I looked
> at my laptop, and some resolutions are supported by cropping. But
> when I selected 800x600, that resulted in a magnified image (and not
> by a factor of 2 either), which implies some re-sampling going on.
> But even knowing that is a possibility, doesn't explain the noise pattern.
> There'd be no process in the re-sampling, that would add noise like that.
>
> The only thing I can think of at the moment, is one wire in the R+ R-
> pair, one wire in the G+ G- pair, are open circuit. And the receiver
> is no longer working on a solid, differential signal. Those signals
> would be on the ribbon cable, between motherboard and panel (and
> through the hinge).
>
> Just a guess,
Probably a decent guess, with the open occurring at the connector on the
motherboard. Just for completeness (as it's been solved) I'll comment
that the effect appeared to be unaffected by resolution choice.
Re: Palette Shifting Craziness on Laptop Screen (Solved)
Grinder wrote:
> Problem solved. Apparently the motherboard connector that accepts the
> cable from the flat panel is a bit screwy. It's taken a bit of
> electrician's tape, but it seems to be working well now.
Sometimes ribbon cables are soldered down but many times they are used
with connectors. They can't be soldered because they can eventually
break from long-term repeated flexing and need replacing or need to be
removed for servicing other components. Alas, flexing also places
strain on the connection which can lead to the ribbon cable walking out
of the connector hence why tape is often used to affix the ribbon cable
in place to reduce strain on the connection and help prevent the ribbon
cable from walking out of the connector. Most times the ribbon cable
just slides into a connector or a connector affixed to the ribbon cable
just slides onto another connector; however, they don't provide holes in
the ribbon cable through which prods would extend when locking down the
connection to prevent the ribbon cable from walking out or some locking
mechanism between a soldered on end connector on the ribbon cable and
the mating connector on the PCB to ensure they don't work apart. That
costs more money (a few cents) so they hope the connection doesn't work
apart by relying just on friction. Yeah, well, they do it that way.
When you pushed the ribbon cable back into the connector, did you seat
it fully and push it straight in?
Has this laptop even been in for repair? While it's possible for a
ribbon cable (the stiff, thin type) to work itself out, more likely is
someone serviced the laptop, disconnected the ribbon cable, and then
didn't push it all the way into the connector on reassembly. I know a
QA guy that worked 2 months (evenings only) on getting his desktop video
working, replaced the mobo (because the AGP slot had a crack in one
corner - that might've been caused by him), which I fixed the first time
I looked at it when he brought it into work just because he didn't push
the AGP video card all the way down into the AGP slot. While ribbon
cables with affixed connectors usually get pushed all the way onto the
mating connector, I've seen the slide-in ribbon cables not pushed fully
into the friction connector.
If by using tape you meant the connection is loose for the ribbon into
friction connector, tape isn't going to solve that problem. Can't tell
what "screwy" was supposed to mean or how you used the tape.
Re: Palette Shifting Craziness on Laptop Screen (Solved)
On 12/31/2011 10:31 PM, VanguardLH wrote:
> Grinder wrote:
>
>> Problem solved. Apparently the motherboard connector that accepts the
>> cable from the flat panel is a bit screwy. It's taken a bit of
>> electrician's tape, but it seems to be working well now.
>
> Sometimes ribbon cables are soldered down but many times they are used
> with connectors. They can't be soldered because they can eventually
> break from long-term repeated flexing and need replacing or need to be
> removed for servicing other components. Alas, flexing also places
> strain on the connection which can lead to the ribbon cable walking out
> of the connector hence why tape is often used to affix the ribbon cable
> in place to reduce strain on the connection and help prevent the ribbon
> cable from walking out of the connector. Most times the ribbon cable
> just slides into a connector or a connector affixed to the ribbon cable
> just slides onto another connector; however, they don't provide holes in
> the ribbon cable through which prods would extend when locking down the
> connection to prevent the ribbon cable from walking out or some locking
> mechanism between a soldered on end connector on the ribbon cable and
> the mating connector on the PCB to ensure they don't work apart. That
> costs more money (a few cents) so they hope the connection doesn't work
> apart by relying just on friction. Yeah, well, they do it that way.
>
> When you pushed the ribbon cable back into the connector, did you seat
> it fully and push it straight in?
This particular cable is not a ribbon cable. It's a bundle of
conductors wrapped with metallic tape, and terminated with a plastic
connector that mates with another connector on the motherboard.
After exposing the connection, I inspected it carefully to see any sign
it was not properly seated. It looked like it was in place, but I
popped it loose anyhow. I inspected both connectors to see if there was
any damage, corrosion or dirt. Both halves looked fine.
I re-seated the connector, it appeared to be in the exact orientation it
was when I first inspected it. After reassembling and powering up the
laptop, I could see the video was now good. I put a little black tape
in place in an attempt to relieve whatever stress presumably made the
connector walk off.
[snip]
> If by using tape you meant the connection is loose for the ribbon into
> friction connector, tape isn't going to solve that problem. Can't tell
> what "screwy" was supposed to mean or how you used the tape.
I don't really know what was wrong with the connector, as it appeared no
different in the working and problematic states. It does, however,
appear to be the source of the problem. (Thought I suppose there could
be a break in one of the conductors that I have only accidentally
repositioned into making a connection.)
Re: Palette Shifting Craziness on Laptop Screen (Solved)
On 12/31/2011 8:31 PM, VanguardLH wrote:
> Grinder wrote:
>
>> > Problem solved. Apparently the motherboard connector that accepts the
>> > cable from the flat panel is a bit screwy. It's taken a bit of
>> > electrician's tape, but it seems to be working well now.
> When you pushed the ribbon cable back into the connector, did you seat
> it fully and push it straight in?
Got into this thread late, just adding my 2˘
Some of those ribbon-cable connectors also have barely-visible pull-up
latches on one side. They won't prevent you from pulling the ribbon out
(just takes a little more force to do that), and you can often push
enough back in to make the connection work .... for a while ....
But it won't last! Been dere, dun dat.
Feel both sides of the connector for a ridge along the top and see if
that ridge will pull upwards *carefully*. You might be able to do it
with a fingernail, but a small hook is better. Pull up each end partway
and work back and forth on the ends until it's open all the way.
(Think of gently rocking it out)
When reinserting the ribbon, keep the latch-piece pulled up until the
ribbon bottoms out, then carefully press the latch back down, partway on
the ends, rocking it back in.
These latches are easily broken, and the 'tape fix' is one kludgey
repair method seen. I've seen this done on brand new gear.....
--
"**** this is it, all the pieces do fit.
We're like that crazy old man jumping
out of the alleyway with a baseball bat,
saying, "Remember me mother****er?"
Jim “Dandy” Mangrum
Re: Palette Shifting Craziness on Laptop Screen (Solved)
On 1/1/2012 12:56 AM, Nobody > (Revisited) wrote:
> On 12/31/2011 8:31 PM, VanguardLH wrote:
>> Grinder wrote:
>>
>>> > Problem solved. Apparently the motherboard connector that accepts the
>>> > cable from the flat panel is a bit screwy. It's taken a bit of
>>> > electrician's tape, but it seems to be working well now.
>
>
>> When you pushed the ribbon cable back into the connector, did you seat
>> it fully and push it straight in?
>
> Got into this thread late, just adding my 2˘
>
> Some of those ribbon-cable connectors also have barely-visible pull-up
> latches on one side. They won't prevent you from pulling the ribbon out
> (just takes a little more force to do that), and you can often push
> enough back in to make the connection work .... for a while ....
>
> But it won't last! Been dere, dun dat.
>
> Feel both sides of the connector for a ridge along the top and see if
> that ridge will pull upwards *carefully*. You might be able to do it
> with a fingernail, but a small hook is better. Pull up each end partway
> and work back and forth on the ends until it's open all the way.
> (Think of gently rocking it out)
>
> When reinserting the ribbon, keep the latch-piece pulled up until the
> ribbon bottoms out, then carefully press the latch back down, partway on
> the ends, rocking it back in.
>
> These latches are easily broken, and the 'tape fix' is one kludgey
> repair method seen. I've seen this done on brand new gear.....
>
Good advice, but I just want to clarify that in this case, the connector
does not have a latch. It is a full-blow, two-part, mated set of
connectors--not just a plastic ribbon cable that latches into a
motherboard socket.
Palette Shifting Craziness on Laptop Screen 
Linear Mode
