For the past few months I've had this problem where my monitors will turn black when I'm playing a game. It happens anywhere from 10 minutes to an hour into game play.
This has happened to me in CoD4, Oblivion, and Operation Flashpoint: Dragon Rising. It probably will happen in almost any game, but those are the only games I've been playing recently.
I can play Oblivion for hours without it happening, Call of Duty will usually shut off 30 minutes-1 hour into game play, and Operations Flashpoint will shut down less than 10 minutes into game play.
There is no sound playing when this happens, only in Oblivion. My computer will completely lock-up and there is no way for me to alt-tab or open task manager or anything to get out of it. I am forced to hold down the power button and wait for my computer to shut down.
My drivers are up to date.
I don't really know which specs are helpful in situation so I'll just kind of list what seems important:
Windows 7 Ultimate 64-bit
GeForce 9600 GT
nForce 750i SLI
Intel(R) Core(TM)2 CPU 4300 @1.80GHz
GPU is 53 degrees C when idle and 63 degrees C when playing a game. It can't be the temps because my BIOS settings make it so my PC will beep and shut down if it over heats, and my computer isn't shutting down, the screens just go black.
I have dual monitors that both run at 1360x728. It doesn't make sense that it could be the resolution because I can play the games for a while before they shut down and I've run my PC at this resolution with the 9600GT for over a year without any problems.
I'm not sure which power supply I have, I'll get back to you on that. My boyfriend knows, but he's in class right now. I opened my case and from what I could read it said "MD-600SCPS"... I also think it says intel