My neighbor gave me a gift of 3 relatively new motherboards along with an Athlon xp 2200+. I was sure I would soon crawl out of the Pentium1 dark ages! I baked it on my first bootup. I had a fan and heatsink with the compund spread so it wasn't in excess, so I'm suspecting it was the fact that I didn't see the little switch on the back of the power supply that said 230v instead of 115v... Am I correct? I don't want to make this mistake again.

I think that may be the problem but not totally sure on that. I have never done that before. It could also be the PS itself that is bad.

I don't think you'd fry it just because you picked the wrong voltage. The PS should be able to handle that scenerio and protect the rest of your system.