PSU is new and should not be any problems. I’ve been running GPU on windows 7 without problems (I was never playing BBC2 on Windows 7). And GPU did not print out any errors, event logs or any other warning. I tested all parts of my PC, cleaned it twice, bought new thermal paste for CPU, and system still shutdown. So I downloaded MSI Afterburner and checking temperature. I opened Battlefield Bad Company 2 and started playing. At first, everything was fine. GPU increased temp. from 40C to 50C and keep it at 50C for next 10 mint… Then suddenly MSI Afterburner wrote temperature 0C. Afterburner was recording 0C for next 10 mints and then PC shutdown. Later on, I did another test. Again opened BBC2 and temperature was 0C again. I wanted to go in MSI Afterburner and check what’s going on and manually force fan to 100% speed. But I was not able to do that. Once Afterburner printed 0*C I was not able to exit game anymore. I always got black screen and had to restart PC.

I was trying to install Windows 7 on second HDD and test if problem is with drivers. I deleted by mistake System reserved HDD and had to reinstall Windows 8. I carefully installed new drivers and avoid installing drivers which are not strictly Windows 8 supported (Before I installed drivers for Windows 7 if I could not find them for eight). Now GPU is running with almost 10C lower. When idle temperature is 32C and before it was 41*C… I am installing BBC2 again and will test it. I hope it was just problem in some drivers.