Bought my desktop machine about a year ago, to the day. The video card has started misbehaving, causing certain pixels in the display to just stay one off-color, and to leave trails on any window that gets dragged across them. See these for reference:
I made those patterns by just dragging the windows around across the bad pixels, and the longer the computer was on, the more pixels started doing it. At one point, as many as 40 were wigging out, in turquoise, a pinkish-red, and yellow. I thought I was screwed and would have to return my video card, or replace it outright.
As one not content to just take the easy (and expensive) solution, I spent today screwing around with the computer, trying to make damn sure what the problem was before dropping potentially another $250-300 on a piece of hardware that might be fixable.
I tried switching cables. Same thing. Changed monitors. Same thing. Tried another computer on both monitors, found no bad pixels in the monitors themselves. Thus, it MUST be the video card or the motherboard at large.
Sometime during that tinkering, I got a blue screen of death (BSOD), and my computer magically restarted itself. Later, I fired up Google Earth to look something up and POW it froze.
I reached for the scalpel (i.e., screwdriver) and started taking Betsy apart. Opened the case, pulled out the video card and sound card, moved the sound card down to the bottom-most slot to hopefully give the video card more room to breathe (those things run hella hot). I tried this once before without luck, but this time the comp recognized the sound card okay and just had to reinstall the sound drivers.
I took a good look at the video card for any signs of breakdown, or smells of smoke from overheating. It looked fine, save for a few flecks of dust here and there, so I sprayed it with compressed air. Then removed the heat sink and fan from the card to see if any clues lie inside there. Nope, so I screwed that back together.
Perhaps the card wasn't seated properly in the slot on the motherboard. I situated it, fired the machine back up, and nothing had improved.
Next big idea was to take a room fan and point it straight into the case (with the side still off) to push all that mofoing heat out and see if the heat trapped in there made a diff. Strangely enough, the bad pixels started disappearing.
I let it vent for a few minutes, then fired up World of Warcraft (the last trigger for a catastrophic unplanned restart). No problems. Turned on the frame counter and it was staying solid at around 60 frames per second.
Switched back to Windows Explorer and dragged the window around the screen to see how many bad pixels we had. I only saw one or two.
Back to WoW for about another 10 minutes. Kept the fan blowing. Toggled back to WE. Down to one bad pixel, and barely at that.
I shut the fan off and kept playing WoW to see if the number of pixels would go back up. It did not. In fact, the one bad one seemed to taper off and barely be there at all.
An hour later, with the case back sealed up and everything running as it should, I no longer have any bad pixels on my screen, and have had no crashes.
Say it with me, folks. "What. The. Fuck."
So apparently all I needed to do was move the sound card away from the video card so it could vent better. Let this be a lesson to you. I just saved myself $250.
You never know what tomorrow will bring, though, so I'll keep you posted.