Possibly

Have you tried re-seating all the connectors on the boards? - if you havent re-pinned the connectors there could be an issue here as well.
I'd look there first.

I haven't repinned all of them yet... only the ones that connect the power supply and the display ones on the right of the CPU. The fact that it worked great at first made me think it was the board...it's frustrating as I can't get it to startup at all now.