Recently (the past two days), I have been experiencing graphical glitches. Seemingly random pixels (often in a horizontal line or rectangular group) would flash incorrect colors (like stuck pixels, except their color can change and they appear and disappear).

By removing my NVidia 8500 GT (falling back to the integrated 6150LE), I have removed the symptoms (except that now CAELinux doesn't display anything... but everything else works).

I suspect that it is the graphics card (I'm aware that the cards have known overheating issues), but I want to eliminate any other options before buying another. Could these symptoms be the result of a motherboard failure?

Thank you for any help.

EDIT: I forgot to mention that it also locks up frequently with the card in (the graphics will freeze, but the caps lock light doesn't flash like it would in a kernel panic).

From my experience I am sure that it is the graphics-card, not the motherboard. At the time I worked in a repair station it was in such cases to 99% the graphics-card.
But there is no way to be really sure than to try a different card.

By the way, the overheating issues you mention were with the mobile versions of these cards.

Just to check...

You could run a motherboard function test using the built-in 6150LE chip test by downloading and booting a live-cd copy of PCLinuxOS with its already configured Nvidia driver to see if the problem is indeed the 8500GT.

I have an 8600GT on which I installed a good passive cooler and found that the cooler was better than the original fan for holding the GPU temperature low(42C) and there is no noise. I expect the 8600GT card to last a long time, at least I won't be cooking it to death.

http://www.arctic-cooling.com/catalo...ath=2_&mID=105

When do the glitches happen, after running the computer for a while ? or under heavy load ? Do you have access to GPU temp info (via nvidia-settings or some system monitor) ?

It is most likely the video card, but like said above, you cannot be 100% sure unless you have another card to try. You mentioned an integrated card ... does the same thing happen with that ?

I've booted Sabayon, Puppy, and Ubuntu fine on it without the 8500GT (no issues whatsoever on integrated).

However, I don't feel that this rules out a failure that only affects the PCI-E bus going to the graphics card.

These glitches happen constantly. During booting, these often aren't seen, but it appears (to me) that this is because they haven't had time to occur. It seems as if these glitches happen randomly when a drawing operation is done (and are kept as part of the resulting texture, until it's redrawn).

I do not have access to GPU temp info (as far as I can tell, none of these distributions can read the temperature). However, I will point out that when I removed the card (to switch to integrated graphics), I found a large amount of dust jammed in its tiny heatsink (which I blew out with an air can).

Thank you for the help.

Have you tried your live distros with the 8500GT, to see if it is a driver issue?

Yes, with Ubuntu 9.04, Puppy 5.11(?), and Sabayon (don't remember the version).

The most likely...

It is possible that the card bus or mounting slot on the motherboard is faulty, but on balance, of the two, the connection or the card, isn't a defective card the more probable?

If you want to be through, see if you can borrow a graphics card and try the motherboard with an installed card, but were it I, I would look around for a used Nvidia card.

Here in Copenhagen, I look at a couple of on-line sites for gamers and overclockers for good hardware bits and pieces. They're always switching their once was the best but now is not good enough graphic cards in favor of what is now the best, and selling off what once was.

Oh, to be seventeen again.

Very good, "recycling" is always a good idea. Just keep in mind that it can be necessary to get a bigger PSU if you buy a "real" gamer card.

Truly, I smell a gamer...

A hefty PSU is surely a boon. I bought the at the time best reasonable one I could, a Corsair HX620 and it loafs along at low temperature. Low voltage or a failing PSU can produce so many untraceable faults that you'll grow old chasing them down and never get to go outdoors to play in the snow again.

Okay, I guess I'll get a new graphics card.

I think I'll get an ATI, since the open source drivers are "better".

Thanks for the help.

But,but...

The Nvidia propriety driver still performs better. Do but what you will.

I can't recommend ATI.