7VAXP board taking out power supplies?? HELP!!!

OK, I just got a Gigabite 7VAXP board with an Athlon XP 2000 processor and 256 PC3200 Corsair ram. I took the mainboard out of my current PC and installed this new board. Went to turn on the PC and all I get is a small audiable electronic buzz, the fans make a couple of turns and thats it. To troubleshoot I unplugged everything except for the ATX power cable to the M/B and then it powered up okay. So, then I started plugging stuff in one buy one and everything seemed to work. Everything seemed ok??? YA RIGHT!!

I went on to load the O/S did some testing and so on, everything worked fine. I got up the next morning and decided to try my buddies Geforce4 TI 4600 card. Plugged it in installed the drivers and went on to test. Right in the middle of the test the PC just shut off. Went turn it back on and I was back to the very first problem. Small buzz from the power supply, fans turn a few times and thats it. Tried another power supply, it came up okay so I started the testing again and bam everything shut off again. I have tried EVERYTHING to try and get the board to power on again, no go.

I then took the two power supplies and pluged them in to another known working system and now they will not power on, both power supplies dead. Both of the power supplies are Codegen 350 watt.

So, has anyone ever heard of a mainboard taking out the power supply? I'm thinking that a 350 watt supply should be plenty for this setup but now I got what seams two dead power supplies.

Should I go and get a 450 watt supply and try that? Or is it the Gigabite board the cause of this problem???

Please, any input would be much appreciated.