Stuck on post code 25

[Troika]

So, I just acquired a old XFX nForce 780i SLI board that was in good physical condition. The only apparent issue was a bent pin in the cpu socket, which was easy to bend back into proper place. The first cpu I tried to see if it worked was C2D E8500 but got code FF a few times. Changed psu to a known good one and same issue. I tried a different chip, another E8500 chip and got some progress. The codes went FF -> C1 -> C3 -> 25 and I get stuck there. I couldn't find documentation for XFX's board, but EVGA's variant of the board is identical. I'm pretty sure EVGA makes both theirs and the XFX variant since the layouts are the same. According to EVGA's documentation, post code 25 Shadow system/video BIOS. I can't really find much on this particular issue, with most threads I found said their boards were RMA'd or that it could be a dead northbridge chip. I'm hoping someone here might have some idea as to how to proceed. I'd really like to get this board working, I have a QX9650 that I'd love to socket into it and see what sort of results I can get out of it.