Hello,

Just recently purchased a used S9, 1 board not hashing. I had the previous owner reboot the device and saw it come back to hashing on 2 cards. He had it hooked up with an APW3++ to 220v. I brought it home, hooked it up to the APW3++ on 110v, but left the non hashing card unhooked (knowing the power limitations of the APW3++ on 110v). Here's what happened:

1. I let it sit for over an hour. No hashing. Checked the kernel log, recognized both boards, but started cycling through checking the fans and said "Fatal error: fan speed too low"
2. Unhooked I/O cable for 2 boards, leaving board #1 connected. Boots up, starts hashing within 5 minutes.
3. Disconnected board #1 and connected #2, started hashing with 5 minutes.
4. Hooked both boards back up, kernel log shows fan error.

Any ideas?