New computer won't boot...is this a bad motherboard?

[kafro]

This is about the 4th machine I've built from scratch, so I'd like to think I know what I'm doing, but this machine just won't start.

When I turn it on, the 2 chassis fans and the CPU fan spin, but not my graphics card. When I put my graphics card in another computer, it spins and works perfectly. When I have plug the graphics card into my new PC mobo, but have it's power coming from a 2nd computer, it also does not spin. (So I don't think its a PSU issue, or a graphics card issue).

There is an onboard graphics card and when I plug my monitor into that, I get nothing either, which makes me think it is a mobo issue. The green light on the mobo lights up when it is recieving power, but does not make any beeps, even without ram.

Could anything randomly be causing this, like some incompatible hardware or maybe not ground it correctly, that would do this? Or is my motherboard just bad?

I made sure everything was compatible first, but here are my specs:
AMD Phenom II X3 720 CPU
ASUS M4A78T-E AM3 Mobo
OCZ StealthXStream 600W PSU
OCZ Platinum 4GB DDR3 1600 RAM

I'm stumped otherwise....any ideas?

Thanks!

 

[shortstuff_mt]

Have you gone through this checklist yet?

http://www.tomshardware.com/forum/261145-31-read-posting-boot-problems

#2 on the list is the most common cause of problems like yours.

 

[kafro]

Yes, I connected the 4-pin ATX12V slot on the motherboard with a 4-pin cable from my PSU labeled CPU1 and also tried with CPU2. No luck...