Pc freezes during games

[kregstrong]

ok so ive been having this problem for a while with certain games. i will be playing and randomly my computer will just freeze and make this loud continuing noise through the speakers until i hold the power button to shut it off, screen goes black. i have tried all kind of stuff to fix this, defrag, registry clean, monitored temperature, upgraded ram, and still no luck. ive been playing far cry 3, and i can sometimes play for 20 minutes before a freeze or an hour, then sometimes i can play for 2 hours and nothing happens. can anyone give me some suggestions cause im getting pretty frustrated. and also im coming off a freshly formatted hard drive with windows 8 installed now. running steam, core i5 2500k, 12gb ram, 2 gtx 660ti, cx600 psu. could it be the power supply?

 

[wanderer11]

Well what were your temperatures for gpu and cpu? I have heard Far Cry 3 is buggy, so does this happen with any other game/program or just Far Cry?