Problems with A8N-SLI Premium

[Gophinx]

Hi, I've been having problems using a 8800 GTS with this mobo, and I though that I'd reset the BIOS just to see if that would make any difference, but it didn't so I plugged my old graphics card in and went to start switching on RAID etc in the BIOS, made all the changes I wanted and then save change and exited but then I got no signal, so I reset the BIOS again using the jumpers and then tried a make a few key changes to get the system running. And the same things happens over and over, reset the BIOS make some change then no signal it's an endless loop at the moment. And if that's no bad enough I've got an assignment due in tomorrow on one of my RAID drives and I have no idea if I get the system working again if I'll be able to boot windows and finish the assignment