Gigabyte mobo > MB GIGABYTE|GA-MA785GMT-UD2H 785G R
EVGA graphics > VGA EVGA 512-P3-N954-TR 9500GT RT
Thermal take PSU > PSU TT|W0116RU 750W RT
AMD Athlon processor > CPU AMD|ATH II X4 620 AM3 R
4g Gskill ram > MEM 2Gx2|GSK F3-10666CL9D-4GBNQ R
Seagate hard drive > HD 500G|SEAGATE ST3500418AS
Whenever we plug anything up we cannot get power. We have tested the power supply and get fans and CD drive to work when it is not plugged into the mobo. However, once plugged in we get nothing. We returned the mobo thinking it was defective, but now the second mobo is having the same issue. We have double checked all installation on the mobo and it is done correctly. Is there some sort of compatibility issue with PSU? I've been looking around the internet and have not yet found any such case.
Any insight would be appreciated and thank you in advance,