Problem with computer randomly restarting! PSU?

I have the Intel monitoring software for my motherboard, and it's popping up warnings about my CPU core voltage being out of range, plus the +3.3, +5 and +12 being out of range, and my fans running unusually slow, 700rpm.

I just installed a new Antec 550 neo HE.

My system is:
Intel Prescott 551 3.4Ghz
1Gb DDr400
120 gb IDE HD
3 Fans(2 case, 1CPU)
x1800xt

Also, I had a power supply literally explode in my machine while maxed out on quake 4, and that was with a 450W generic supply. I replaced with the Antec, and I'm still getting random reboots, and these power discrepancy messages.

Is it possible that I simply damaged the motherboard? I've inspected each component, and everything looks fine. Heat is fine right now, so I don't believe that is an issue.

My question is what could be causing these errors? Is it the new PSU? Is it the Mobo? Help please!

-Aaron

Any suggestions as to what may be the cause? Can heat cause voltage variations? What about the power strip my PC is plugged into? I know this is going to sound lame, but I also have a window unit air conditioner plugged into the same outlet, although it isn't plugged into the power strip where my computer is. Any thoughts?