OK, found a little more information on the motherboard.
It's an ECS K7SEM (PC Chips M810LMR) w/ a SIS7018 chipset. Still not sure what the specific BIOS is on it, but I'm almost positive it has never been updated.
A Tech site on this motherboard (http://radel.inet.net.nz/m810lmr.html
) suggested using a beefy power supply when using an AGP card (the motherboardboard has onboard VGA) and forcing 1X AGP.
As soon as I get off of work, I'm going to swap the PSU for a 400W and try updating the BIOS. As for 1X AGP, I'm not certain this is something I can do from the BIOS (the site I found indicates that for windows users, a registry hack is the best way to do it)
Does anyone know of a software method to force 1X AGP? Is this one of the options I can pass to the nvidia driver in xorg.conf?
I'll update this as soon as I can try those out.