Mainboard troubles

I have had this particular system up and running since January or so. Tonight it will not go to boot, it just displays the messageress Shift-Tab to try network boot, Try other boot devices
then it just hangs. So i disconnected the power supply and shorted the CMOS. I got it to boot up once and tried to restart after making the appropriate checks to run the Bios setup program and it does the same thing. MSI support says not to use an XP-M in the board, but i dont think that is the problem considering the XP-M is a Barton Core and has an unlocked multiplier. I set the BIOS FSB to 133 just as the processor is intended to be set. It is identified as an Athlon 2800XP-M Speed 2133mhz. No problem there. Is there anything i can do short of yanking the board and trying another to see if that is the problem? I really like this mainboard and the flexibility it gives me and hate to give it up. Any help would be appreciated.