To fix the problem, you need to change the CPU to one that runs on a 100MHz FSB. The current PIII-667 uses 133MHz, and the board just can't run with that. A Google search will confirm this (MEW-AM).
You *may* need to update the BIOS to accept the CPU you purchase, as later steppings were added along the way. I chose not to use the latest BIOS, but an earlier version that contained more *features*.
I have a post on this here in the forum. If you need more info, just post here and I'll drag out the exact things I did to *fix* mine.