Anocer OC question

[JD50]

So I just rebooted after going from 2.6 ghz (running stable at 2.6) to 2.8 ghz and I get no video. The only thing that I changed in the BIOS was the FSB from 260 to 280, saved, then rebooted. I got to the ASUS screen where it froze, so I rebooted again and I got to the screen that asks how you would like to boot because of a previous system failure, picked the normal boot, it froze again, and now when I try and boot I get nothing. All of my fans are running, mobo light is green, no beeps, but I don't get any video whatsoever. I tried a different monitor, and I tried moving the video card to the other PCI-e slot, still nothing. Any ideas?

System specs -

ASUS P5k (normal, not deluxe)
C2D e4400
500w antec PSU
nividia 8800 gts 640 mb
4gb OCZ DDR2-800
Vista home premium 64

 

[JD50]

Ok well its booting now....I had taken out the CMOS battery for a few minutes to try and reset it, but it still didn't boot after that. I stopped working on it for about 45 minutes, came back, and it booted, although I did get the "overclock failure" screen. Which is kind of odd, since I didn't think I would have much of a problem going over 2.6 ghz without upping the vcore. So, I have no idea what happened, but it seems to work now.