I just got my HD 7770 in the mail today and slapped her into the PC. First boot was a little slow, but got into Windows with the card in the Device Manager as an Unidentified VGA Adapter. During the installation of the latest ATI drivers (straight off their website), right during the 'identifying hardware' segment of the driver installation, the system hard-reset. During the bootup after the reset, the PC failed to POST and was sitting at a black, blank screen with a blinking cursor in the upper left.
From then on, powering the PC on has produced a power-on / power-off loop that never makes it to POST and does not have any VGA signal output to the monitor.
Dismayed, I replaced the HD 7770 with my old HD 4850. The same power-on / power-off loop occurs.
The mainboard is a Gigabye GA EP-45 DS3L. The CPU is an Intel Q9450 overclocked to 3.2 ghz, running alongside 4 gigs of RAM. Powering the whole shebang is an Antec Earthwatts 500w power supply.
I am having a hard time figuring out why the system would boot to windows at all if there was such a problem... Further, why driver installation was the moment of failure... And finally, what kind of failure would produce the restart loop that I am in...
Halp!
