I found that PSU for sale for $18. A reliable 400W PSU would cost $50 minimum, so I would guess that your power supply is a least part of the reason why you are having this problem. I would replace it with an Antec True Power 380W with 24A on the 12V rail. Of course there are plenty of other good brands out there, so check out the PSU guide in my sig for alternatives, and the brands not to buy.
Power Supply Guide
' ">http://www.hardforum.com/showthread.php?t=792566 Memtest86
' ">http://www.memtest.org/#downiso Prime95
' ">http://www.mersenne.org/freesoft.htm SuperPI
' ">http://files.extremeoverclocking.com/file.php?f=36 3dmark05
' ">http://www.futuremark.com/download/?3dmark05.shtml CPU-Z
' ">http://www.cpuid.com/cpuz.php#download <