Ihave been successful in building and asusm4a785td board 700w ocz 4Gb Gskill ripjaw AMD Phenom2 x6 with xp sp3 setup. I installed a sapphire vaporx 5770 video card and the pc won't power on if I remove the card it will turn on. I am sure my psu is fine is my card dead or should I try something, if do what?