Have a bad hash Board?  Think Again....
I moved one S9 from a garage to in the house.  Plugged it back in, hash board not hashing. Wow..  my luck.

So after several reboots, firmware downgrade resets, etc. I found one post that mentioned power issues....

They say a APW3++ is insufficient for a S9 on 110/120 volt.  Well. I beg to differ, I have had them running for months like this..  several of them in fact.

Chain 5 was the bad one, I moved chain  5 from controller to middle hash board, found that now that hash board did not work, but the original one did.

Thought, well someone said it didn't have enough power, tried different PSU ( New one as a spare)   Same issue.  Hash boards all worked, just that CHain 5 from controller did not work.  Bad controller?

Plugged in the other PSU to power one has board Middle hash board connected to chain 5 ( Swapped from chain 6)  Powers up, boots, hashes on all 3 boards.  Hmm weird.

Put back so that CHain 5 6 and 7 are in sequence again as original, still powering middle hash board with 2nd PSU,  Boots, only two hash boards hashing ( Chian 5 is not)
Power up first hash board ( original Chain 5 connected to chain 5 ) and still onloy two hash boards hashing, BUT NOT THIS CHAIN 5.

Plugged in chain 5 from controller to middle hash board, powered this middle has board with second PSU, boots, hashes no problems.

So I cant figure out what is wrong.  All the components work, but the first hash board does not like Chain 5, it likes to be on chain 6 with a separate PSU.  Will not work with one psu even if fist hash board is still on chain 6.

Any ideas?

FYI, This posted for those who think they lost a hash board... Which I initially did, but was somewhat relieved to see that it still works.  So you may want to trouble shoot more before you decide bad hash board.

To complicate things even more, just After i first saw this happen to this S9, I had two others experience the same thing, but 20 and 30 minutes after this one did.  Both lost one hash board. But a factory reset on the one, and reboot on the other fixed those.

Confused.