one board literally does not hash no matter what port or cable i use or clock speed, i tested this with the other fully disconnected. I was looking in the kernel log and its reporting power error. I tested the vdd's and they are all the same as the working board, so maybe its something else.
edit:
Its not hitting 80c, its barely breaking 55c for me. I'm just saying the guy said it got hot and shut off on him.
Your boards are gone. This is big mistake of BITMAIN, their S5 even they stop mining, the are the same power of like when mining. If your miner overheat, the chips are very good piece of silicon, they survive, but they melt soldering and desolder power pins. At least two of them are desoldered. You can use regulated power supply, set it max. to 8A and 9V, set 100MHz and start your S5.
Try to press every bottom side of each ASIC, you will probably find two desoldered which pressed are temporarily working. Do not try it at full Amps or at 12V, it may brake your PCB.