I have recently bought a HD 5770 ATI video card replacing my current 8800GTS and burnt 275GTX video cards. I uninstalled everything nvidia related in my computer (windows 7 64bit), turn PC off then replaced video card... turn pc back on and all I would see is a blank screen. No bios, no windows, no nothing. I sent the card back for replacement thinking it was a bad card, turns out they tested the card and its perfectly fine and they are now returning it to me. Could someone please tell me what is going on here?