Hey guys I just built my computer and it seemed to work well at first. But after some stress testing with my 9800 GTX+ it started doing rainbow snow effects. It seemed to do them after a little period of working normally. Now today the computer keeps restarting extremely quickly whenever I play graphically intensive games (rainbow snow seems to have disappeared) and after a couple hours in desktop mode. The power supply is a BFG rated at 550w with quad 20A 12V rails so I think it should easily supprot the 9800, but could either or both parts be defective?