Biostar P4M80-M4 shuts doiwn and restarts

I have a Biostar P4M80-M4 and it will boot up and then not long after that
it shuts down and then tries to boot up again on its own. It will do this a
few times and then stops doing anything completely. I am thinking maybe a
heating problem but the CPU fan seems to be working properly, although i am
not sure it is is fast enough. I had this same condition on the original
Gateway board and replaced it with the Biostar, but the same problem occurs.
Leading me to the fan or maybe the on off switch. I did unplug all the
boards and CD Rom which didnt help. My question is this...

Does anyone know if this board has a monitor utility built into it and if so
how do i get to it? Or maybe someone could offer up some other help ideas.

Thanks