ok so here is the deal. i play WoW and yesturday my computer turned off out of nowhere while i was playing. So i figured out that it turned off when i played any game. i check i have no viruses. i have a amd 2 ghz, ati 850 xt crossfire. and i just cleaned out the dust and it helped out a bit but still does it but lasts for about 40 mins b4 it turns off.