Here are the symptoms, tell me whats dying

[TecHNooB]

On my desktop, I see pixels changing colors (it's a uniform spread across the screen). This doesn't always occur. Sometimes it does, sometimes it does not. When I play a game like bioshock, battlefield 2, css, etc, the videocard(?) crashes and my monitor will display 'Signal not found'. I think at one point GPU recover would kick in but it no longer does and I have to restart the computer.

I have an Earthwatt 430W PSU and an X1800XT vid card. I also have 250GB, 400GB, and 750 GB harddrives. At the time, I didn't make wattage considerations so I might be overtaxing the PSU.

 

[happy medium]

Card overheating or bad video ram.

It's possible it could be the power supply but not likely since on your desktop your seeing artifacs.

 

[Jacky60]

It may be your optic nerve

But it may also be your video card

 

[taltamir]

its UNIFORM across the ENTIRE screen? sounds like contacts (in the cable) problem. also with the going to "no signal found"...
now, if it is not perfectly uniform across the entire screen then I would call it "artifacts" and it would be an indication of your video card failing (either due to lack of power, due to PSU failing, or due to it itself failing)

 

[Rifter]

Things i would check in this order:

Video Cable
Video Card
Memory
PSU

 

[taltamir]

Things i would check in this order:

Video Cable
Video Card
Memory
PSU

I agree.

 

[Martimus]

It sounds like the cable got jarred loose (especially if it is a VGA cable). Otherwise, maybe some of the wires in the cable have worn and are periodically creating open circuits. If this is the case, you should just replace the VGA cable. If it is attached to the monitor, you can strip it and solder the broken wires, insulate them, and wrap it back up and it should be good as new for a while.

 

[VashHT]

Agree with cable, same thing happened to my old DVI cable. Make sure that it's plugged in completely and screwed in on both ends. If it's an old cable some contacts may be going bad, if I were you I'd just buy a new cable since they're pretty cheap.