EDIT - My friends 5750 seems to be having a problem. I tested it once on my PC for about 30 mins and it worked fine but later on when i tested it again, it crashed. After about 20-30mins the display goes black. And the fan starts to rotate fast.(Probably at 100%) It's not a problem with the mobo or PSU. Is there any way i can fix this? And the warrant period just finished.