Help with a BFG 9800GT OC+

I have installed a BFG 9800 GT OC+ but can only boot into safe mode and VGA mode.

When trying to set it to any resolution above 640x480, 8-bit,my Princeton 17" flat screen
flashes silver briefly when loading Windows and then I get an amber power light and a black
screen. If I boot into low res. and it suggests Windows change the resolution, I get the
same thing. Same thing when running the install on the drivers. I'm thinking it's trying
a resolution the screen can't handle(?) but every time I try anything above the low res.
it goes black.
I have an ASUS P5NSLI board with an Antec 450W power supply. The power supply has a special
pigtail marked for a PCI-E card. Uh, the mobo has DDR2 memory and the video card has DDR3 memory.
I just upgraded the BIOS on the mobo with no luck and did the wiping drivers routine
with no luck


Help?