So I was able to get some replacement X3 boards from MS (thank you), and I am going to just move the heat sink from the dead one to the good one.
The heatsink for the asic is held on by 4 screws - simple enough. On either end of the board is another heat sink and that one is applied with some type of glue, I tried pulling, turning, twisting, etc, but I don't really want to accidentally break the defective board in the process of removing the heatsink.
I have a heat gun I could try to heat them up, but I didn't want to go too hot and melt anything.
Replacement board
Any tips