Asrock Extreme will not post - help needed

Configuratrion:

Asorck Extreme
i7 920 D0
Scythe Mugen 2 w/ Arctic Silver 5
EVGA 275 GTX 2 in SLI
Seagate 7200.11 750GB
Corsair HX1000
OCZ Gold 1600 8-8-8-24
Case fans x12


So, the computer was working. At the time when it happened had a mild overclock of 3.6Ghz, was running temp monitoring software, CPU core temp never exceeded 72C. I was in Windows Vista 64bit SP2. Was just doing file transfers at the desktop. No 3D applications were running when all of a sudden the whole computer shut down in a similar manner as if someone just pulled the plug on it - black screen with no warnings. No smells or abnormal sounds noted at the time and before incedent. Pushing the power button did not turn it back on. Verified there is voltage in the outlet and plugged power cable directly in it. Tried clearing CMOS with the button as well as the jumper. Tried removing battery and reinstalling it - no change. Went to Corsair web site and read about conducting a "paper clip test" to make sure PSU still working and it is. With paper clip installed all fans are turning and voltage is present on the plugs. When ATX connector is installed on the board and the power button is pushed, initially the fans turn on for a microsecond and then turn back off. No lights turn on on the motherboard. Removed the board from the computer case and inspected front and back of it - looks normal, no wires hanging, no loose washers. Placed it on electrostatic bag and red foamy pad the board came with. Reconnected all power cables, only one video card and hard drive. Verified everyting is tight. Still the same issue - after pushing the power button, fans make 1/16 of a full revolution and then turn back off, while the motherboard shows no signs of life whatsoever. There is a diagnostic LED light panel that shows codes when board is on and manual has a chart to tell what they mean, but it will not turn on anymore.

Unfortunately, I don't have access to another PSU and another motherboard. What are the other things I could do to test what's wrong?

I tried hooking everything up the way the described, and still no beep codes. Speaker was tested and it is good. Board was RMA'd yesterday. Now waiting on replacement. Hopefully the second try will be more exciting...