I have seen many threads like this and have seen that many problems were solved by finding problems pertaining to individual systems. So far I have not found a workaround for my problem. I have the following hardware.
GA-890GPA-UD3H gigabyte motherboard
phenom II x6 1090t 3.2ghz cpu
Ultra LSP 750Pro ATX PSU
Radeon HD 5670 1 gb graphics card
Liteon 4x internal blu-ray disc reader
Western Digital 5200 2 tb hdd
8 gb corsair ram 1333
Thermaltake armor A60 case
Windows 7 ultimate 64bit
Viewsonic 24" led monitor
Nothing is overclocked.
Latest 11.6 drivers
It is a new build and it has occasionally happened on its own just by doing whatever on my computer. The computer turns black for a few seconds then recovers. When I am in a game SC2, it will occasionally happen. But the worst issue is when the graphics card is under a heavy load, (like a big battle in sc2 or a very detailed map loading), the computer screen turns black then refreshes, but I cant move my mouse or anything and the entire CPU is frozen. I have to force a restart. I have unplugged the DVI when this happened and plugged it into a different monitor when it happened and it is just a black screen.
Things I have tried,
Uninstalling and reinstalling the drivers
rolling back the drivers
Uninstalling the catalyst control center
Checking computer temperatures. Nothing goes above 40c, graphics card normally at 32c or so. CPU is about 36c avg.
Putting the graphics card in a different slot. (lol blowing into the cards fan *i know that will help *)
Setting the graphics down on the game. I don't want to put graphics down on screen otherwise I would just get a different card. Whole point of the card and monitor is for perfect quality. (I will for diagnosing if needed)
I have read many fixes on a bunch of forums, but then I read after people try them that it does not work. I read that I can create a profile and overclock the system and it fixes it or something like that but I do not know exactly how to do it. I also read that I could change the Microsoft registry setting (or create one) to set some timeout feature higher than the default 2. These are 2 things I have not tried because I can't get back to the forum with the steps. (lost in history somewhere)
I am decent with computers. Not a desktop expert but not an amateur.