OK. Brand new build here. Installed mb drivers sound, video onboard, etc. and windows SP 1 with most updates, updated bios to latest and updated other mb drivers to latest. System is stable now. So I have put a Asus 760 GTX Direct CU II OC 2 gig card in and tried to install the latest driver v331.65. Windows won't start after reboot. Just a black screen after Bios and windows start screen? I have a ASUS Sabertooth Z87 MB, one stick of 8 gig Patriot High Performance RAM, Corsair 750 Watt Modular PSU, i7 4770K HT 3.50 ghz Processor, H60 Corsair Liquid Cooler that are all brand new. One SSD Corsair Neutron 120 GB HD primary for boot and windows. Checked the drive for error, none. Now I'm not sure why its not working. The two card fans are running, a little green light is on at the base of the 8 pin connector (there is another led that is not on to the left of the one that is) which is plugged into two six pin adapter connector cable. This eight pin to two six pin connectors cable came with the card by the way. Should work as the card is powered and bios only beeps once - short beep after MB checks, Anyway, is it a bad card, wrong power connection, not enough power for the card to run or something else conflicting? Sorry for the book.