Need help with DFI G4S620-N - serial issue

Hi guys,

I was wondering if anyone could offer up some help on a problem I've been having. Basically, I've just built a system with the G4S620-N motherboard, P4 3.06GHz HT and 512MB DDR400 RAM. However, there is a crucial problem with the system, that being:

Sometimes when the system is turned on for an unspecified period (usually a few minutes) it suddenly loses power and restarts. After some digging the problem appeared to be fixed when I changed some serial port settings (disabling the unused COM2 and COM3 ports since nothing is physically connected to the mobo pins). However, COM1 has not worked, no matter what I try to do to get it to work. I *need* COM1 to work as that is a major function of the use of this system.

I've tried letting Windows control the I/O and address settings, I've tried letting the BIOS control them, and I've tried setting them manually (same settings) in both. Yet still nothing works. Any ideas?

Cheers,
DeZmond