I have succeeded to get the 2nd board operational by heating up the machine ( previously he saw 40 of 44 chips and when heated 44/44 ). But it was just a matter of time before it dropped out again. I found out that you can do the same thing with his original paper box if miner can see at least 1 board. ( upclock board, cover with a box, let it run for 10s, unplug from wall socket, re-plug again ).
On the other machine i found the best solution to be the following:
- Machine usually works with 2/3 boards only.
- Up-clock the unit to 800 Mhz.
- Set Disable chips at 92 C.
- Set the unit to downscale if chip overheat.
- Quiet fan mode at startup.
- After it restarts all 3 hashboards are visible ( for a 12hr or a day ).
- Up-clock to 800mhz again but select Pre-save option this time.
[2020/05/01 17:35:06] INFO: Power ON
[2020/05/01 17:35:08] INFO: Starting FPGA queue
[2020/05/01 17:35:08] INFO: Initializing hash boards
[2020/05/01 17:35:08] INFO: chain[2] - Initializing
[2020/05/01 17:35:08] INFO: chain[1] - Initializing
[2020/05/01 17:35:08] INFO: chain[0] - Initializing
[2020/05/01 17:35:22] INFO: chain[2] - 44 chips detected
[2020/05/01 17:35:23] INFO: chain[1] - 44 chips detected
[2020/05/01 17:35:24] ERROR: src/chip139x.c:1006 chain[0] - Failed to receive chip replies
[2020/05/01 17:35:25] ERROR: src/chip139x.c:1006 chain[0] - Failed to receive chip replies
[2020/05/01 17:35:26] ERROR: src/chip139x.c:1006 chain[0] - Failed to receive chip replies
[2020/05/01 17:35:26] WARN: chain[0] - 0 of 44 chips detected
[2020/05/01 17:35:49] ERROR: driver-btm-chain.c:487 chain[0] - Failed to detect ASIC chips
[2020/05/01 17:35:49] INFO: chain[0] - Shutting down the chain
[2020/05/01 17:35:50] ERROR: driver-btm-base.c:358 chain[0] - Initialization failed
[2020/05/01 17:35:53] INFO: Start-up temperature is 22 C (min -15 C)
[2020/05/01 17:35:53] INFO: Activating silent start-up mode
[2020/05/01 17:35:53] INFO: Switching to warm-up fan control (62 C)
[2020/05/01 17:35:53] INFO: Setting voltage from 19500 to 19800 mV gradually
[2020/05/01 17:36:15] INFO: Setting freq from 50 to 800 Mhz gradually
[2020/05/01 17:36:15] INFO: Warming up the chips
[2020/05/01 17:36:24] INFO: Switching to automatic fan control (80 C)
[2020/05/01 17:36:24] INFO: Start mining!
[2020/05/01 17:37:24] INFO: Setting voltage from 19800 to 19600 mV gradually
[2020/05/01 17:37:47] INFO: Setting voltage from 19600 to 19400 mV gradually
[2020/05/02 06:11:10] WARN: chain[1] - Overheated, chip temp=92
[2020/05/02 06:11:10] WARN: Switching to emergency fan control
[2020/05/02 06:11:10] INFO: chain[1] - Shutting down the chain
[2020/05/02 06:11:10] INFO: Shutting down the miner
[2020/05/02 06:11:11] INFO: Stopping FPGA queue
[2020/05/02 06:11:11] INFO: chain[0] - Shutting down the chain
[2020/05/02 06:11:11] INFO: chain[1] - Shutting down the chain
[2020/05/02 06:11:11] INFO: chain[2] - Shutting down the chain
[2020/05/02 06:11:11] INFO: Power OFF
[2020/05/02 06:11:27] INFO: Detected 256 Mb of RAM
[2020/05/02 06:11:27] INFO: Switching to manual fan control (30 %)
[2020/05/02 06:11:27] INFO: Checking fans
[2020/05/02 06:11:27] INFO: fan[0] - OK
[2020/05/02 06:11:27] INFO: fan[1] - OK
[2020/05/02 06:11:27] INFO: fan[2] - OK
[2020/05/02 06:11:27] INFO: fan[3] - OK
[2020/05/02 06:11:33] INFO: Power ON
[2020/05/02 06:11:35] INFO: Starting FPGA queue
[2020/05/02 06:11:35] INFO: Initializing hash boards
[2020/05/02 06:11:35] INFO: chain[2] - Initializing
[2020/05/02 06:11:35] INFO: chain[1] - Initializing
[2020/05/02 06:11:35] INFO: chain[0] - Initializing
[2020/05/02 06:11:48] INFO: chain[2] - 44 chips detected
[2020/05/02 06:11:49] INFO: chain[1] - 44 chips detected
[2020/05/02 06:11:50] INFO: chain[0] - 44 chips detected
[2020/05/02 06:11:57] INFO: Start-up temperature is 24 C (min -15 C)
[2020/05/02 06:11:57] INFO: Activating silent start-up mode
[2020/05/02 06:11:57] INFO: Switching to warm-up fan control (62 C)
[2020/05/02 06:11:57] INFO: Setting voltage from 19500 to 19300 mV gradually
[2020/05/02 06:12:15] INFO: Setting freq from 50 to 750 Mhz gradually
[2020/05/02 06:12:15] INFO: Warming up the chips
[2020/05/02 06:12:25] INFO: Switching to automatic fan control (80 C)
[2020/05/02 06:12:25] INFO: Start mining!