Shorted Motherboard?! Case!?

[blkno1]

OK heres the deal...

Ultra Aluminus ATX Full Tower Case
Ultra / X2 Connect 550W PSU
ASUS A8N SLI-Deluxe
AMD Athlon 64 X2 4400
Corsair 2GB XMS3200
BFG Geforce 7800 GTX OC
Creative Audugy 2 ZS Platinum
Dual ViewSonic VX922 19" LCD
2x Seagate Barracuda 7200.8 250GB
Sony DRU810A / 16x8x16x DVD+RW

Thats the system...
All put together I push power...

Symptoms:
No beeps or "Bitchin Betty"
Case Fans Spin
GPU Fan spins
No Video Signal
DVD+RW does nothing. No spin. No LED blinking.
HDs sound like there spinning.


What I've done.
Tried dif DVD drive, same results
Called Asus tech support, said bad board, I RMA got new board. Same results.
Tried dif PSU, same results.
Took to repair shop. They tried dif MB same results. Out of case my components worked fine on their work bench.

Just got the whole mess back home and am gearing up for another night of frustration. My question is whats the best way to go about troubleshooting this sort of problem? Im sure the computer repair place tried everything, but I told em to stop cause it was gettin expensive, so i thought I try a few more things on my own, Short of buying a new case, and trust me thats the next step...

Thanks for your time.
-bk

 

[gtjr]

check if there is an extra spacer that you put on the case which shorted the mobo to the case,check if the screws is not connected on one of the trace in the mobo when tightened.