From a bare bones kit I put a AMD Athlon II X 3 450 triple core CPU, onto a MSI 760 GM-P23(FX) mother board, into a Cooler Master Elite 241 with 550PSU. Triple checked all the wires and plugged it in w/o the monitor. All the fans (psu,cpu,sys) work great and the disk drive opens and closes. There is no power led light on, and no buzzer sound. No lights at all. What went wrong?