Need serious help please!

I ran into some problems with my motherboard (M7NCD) under clocking my Athlon XP 3200+ at 1.1 ghz, customer support at biostar gave me a bun of ideas on how to improve it. But none worked, the even said you can try updating the bios, but they didnt reccomend it. So I went ahead and updated bios and now it wont even boot up. Everything has power and all the fans come on, but just a black screen, and no beep. Is there anyway to revert bios back to it's old version, or is the mobo finished. Any help would be alot of help, thanks.