A7V400-MX wont start

I know about the bios resetting issue, and I have tried removing the battery, and reseting the cmos, but it still won't start up.

Sometimes it comes on for a few seconds and then stops and that is it. Other times it comes on for a few seconds, then stop, then starts again only to stop again in a few seconds. The on/off button does nothing after that.

I bought two of these motherboards and am populating them with 1400MP's that I had in a old Dual machine. I am wondering if the MP chips could be slightly different than the XP chips, and causing the startup cop to reset?

I have tried 3 different power supplys and they all do the same thing, so it is something to do with the Motherboard/CPU. I have tried both motherboards with the power supply plugged into nothing but the MB.
Nothing seems to help.

Thanks for any suggestions.