I just purchased a new computer a couple of weeks ago. It works great, except for the games.
After 25-30 minutes of gaming, the screen starts shaking, pixels are messed up and the whole system restarts. At first, I tried to install the newest drivers on the nvidia website. That didn't work. In fact, it made it worse, because Windows was starting to act creepy.
I tried cleaning out my drivers in every way possible, but couldn't. I had to reinstall Windows and put back the old drivers.
I read something on other forums, that said that the Anti-Aliasing settings were to blame. I don't about that, because I turned them off.
Heck, I don't blame the hardware, I blame the software. Thanks!
Okay, so I tested out Prey. I played at maximum settings for about 20 minutes. Then it happened again: screen freezes, annoying sound in the speakers, restart. I decided to change the settings a bit and only removed the anti-aliasing. It worked great. I played for about an hour and 20 minutes with no problems.
Then I downclocked my graphics card from 650 / 1600 to the lowest 550 / 1400. I set the AA back to 4x and it works.