Dead Nf-7

I Just bought a new nf-7 and got it on wednesday. Built my computer that day and it was stable. Playing games and all crashed a bit. So i upped the ram voltage to 2.8 and low and behold I get a memeory error on the beeps. Me forgetting that I had upped the volts continue to change the mem in different places. Then I cleared cmos. Turned on computer and I hear a pop and steam came out the middle of the mobo where the ram slots and northbridge fan and agp are. Like that area I didnt bother to turn it on because i dont want to risk my CPU or RAM or be in danger so im going to RMA. Any suggestions on what happened?

You pulled the battery, for a good ten seconds, and THEN it popped? That IS weird. Sorry for the loss, hey $100 is better than a car, or a life.

Didnt pull battery Just the CMOS pins. Mabey i did the wrong thing. Im RMA'ing my memory stick too. I think i got a bad one. I was playing halo at stock speeds and it kept dropping