you should try to find the culprit by isolating hardware..
use as little hardware as you can.. also, does the mobo have a debug LED?
If everything powers on, I feel like it shouldn't be a short. You can try booting with just one stick of ram.
If you have a spare working video card, plug that in. Most likely isn't the CPU as it's rather hard to kill a CPU. There's not much you can do except try to find the culprit by trying different working parts.