Little bit of help?

Ok, let me run over this real quick. Alright, I need some thoughts or advice. I just OC'ed my dual 1.2 athlon MP's on a tyan thunder k7 2462ung to 1.4GHz. I can get to the bios and run for what appears to be indefinetely, but when I try to boot XP stalls after a second or two. It lets me choose to reboot in safe mode or not, gets a few drivers loaded, then stalls on amdagp.sys. I am water cooled and the bios reports 27 C, and I think the chips should hit 1.4 with no problem, that was what I was going to start at. Any ideas before I undo the OC? It's gonna suck cause tyan does not let you change speed in bios, so it's all manual on the chip. the cpu database has plenty(9) of 1.2 MP's above 1.4, some at 1.8v and some higher, I am at 1.8v. I can boot to a 98 floppy, and the bios run fine, but XP is being a b!tch.