Just yesterday I purchased a slightly used ASUS GTX 580 MATRIX from a fellow on Craigslist. I don't suspect any foul play on his part, because he showed me around the workings of the card and showed me how to tweak it in GPU Tweak while we were there. Well, I get home and install it and each time I go to GPU Tweak to overclock (usually if I go over 890MHz) the screen flashes and then a message pops up saying "Display driver stopped working and has recovered." I downloaded the latest drivers and what have you to no avail. It's strange, because I am sure there's nothing wrong with the unit itself.
Oh now for your usages it is fine, and no i doubt the CPU is the issue.
You may beforcing too much voltage to the GPU, this happens on my 480's past 1136mv.
Yeah, I just wanted to be safer than sorry with the CPU when it came to my work. But, could very well be it. This thought just came to mind, is it perhaps because I'm using your standard "from-Wal-Mart" power strip to plug it in to? I've been thinking maybe I should have something with a bit more girth.