Is my motherboard D.O.A.? Or is my problem elsewhere?

I'm building my first computer. I'm having a problem figuring out my bare-bones test isn't going through post. I had everything hooked to my MSI 760GM-P34(FX) motherboard as far as the necessary power cables and the CPU, RAM, Stock Heat sink, and the GPU. The motherboard seems to receive power as the gpu fans spin as well as the heat sink fan but still no post. I RMA'd the motherboard back for a refund and the cpu for a replacement. I then bought a GIGABYTE GA-78LMT-USB3 and i'm having the same problem only i haven't got my cpu back yet. I could really use some help on diagnosing the problem!

Heres a parts list:
GIGABYTE GA-78LMT-USB3 Motherboard
AMD FX-6300 Vishera CPU
Seagate Barracuda 500gb HDD
CORSAIR Builder Series CX600 PSU
GIGABYTE GV-R785OC-1GD Radeon HD 7850 GPU
G.SKILL Ripjaws X Series 8GB RAM