the same hap to me, at first i thought it was the card as well, when running 3dmark vantage, the pc would just shut off, then i looked over my install, and i used the adaptors that were already there for my power connections 2x4-1x8 and the 1x6 from my psu. then i changed them out for the ones that came with it 2x6-1x8 and 2x4-1x6 and no problems at all, i do know that im gonna have to rip that stock cooler off of my bfg gtx280oc and replace it with an aftermarket cooler, 79-85c is a lil hot for me (max of 212f) so yea, thats what worked for me