BleepingComputer.com: first build wont turn on at all

apevia x-cruiser with 500w psu which im using
CPU: E5200
2gb gingle ram
Optical Drive: Samsung 20x DVD-RW SATA
MSI G31M3-F
100gb wd ide
ok so history. i first put this together and the psu started to smoke O_O so i took it back and they put another psu in the case. now ive rebuilt and i plug it in and no sign of life at all.... is it possible the psu smoking and blowing up destroyed the life in the mobo?
ive recheked every single plug, wire etc all in place except for the leds in the case which i plan to do later
am i gonna have to go back and get a new mobo?

A failing PSU, especially a smoking one, can certainly damage internal components. It's possible that some of the internal components were effected, you should test each one individually to see which ones survived undamaged.