If you suspect a short as being the cause of your issue, you can assemble your system outside of the computer case, it will still function outside of the case.
You should have it setup so only the major components are hooked up to the motherboard, then do a startup test run.
Suggestions for what should be hooked up on the first try:
1) Power supply 20/24 pin ATX power connector to motherboard.
2) 4 or 6 pin 12 Volt power connector to motherboard.
3) One stick of RAM in slot #1.
4) Monitor hooked up to VGA or DVI port on video output port.
5) CPU in slot and CPU cooling fan operative.
Test system and see the results.
Results Good?: Skip to step #6
Results bad?: Your RAM module may be bad, try switching to another stick and try again.
Results bad?; You a defective motherboard or there exists a problem with your CPU or you have improper setting in BIOS setup utility.
6) Power off the computer and connect the hard drive to the motherboard.
Power up the computer and enter the BIOS so it detects the addition of the hard drive.
Save changes to CMOS and allow it to boot.
Does it boot properly? Yes? Go to step #7.
7) Reconnect optical drives to motherboard and try again.
Results good?: Add other piece of hardware one at a time and retest the machine.
My flow chart above is not perfect, but it gives you a basic idea how to place the motherboard outside of the computer case and assemble it piece by piece until the problem pops up.
After all this testing is done and you find everything works fine outside of the computer case, this means your motherboard was shorted to the computer case.
Edited by MrBruce1959, 22 September 2011 - 05:18 PM.