Antminer S9 - Chain 0 NaN chips and ASIC RT errors - Boot loop
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Hi, I need help with an Antminer S9 that is currently stuck in a boot loop.
The symptoms:
Hashrate starts at 800GH-1TH and then drops to 100GH before restarting.
The Kernel Log shows ASIC RT errors on chips 29 and 57.
Chain 0 reports NaN status on chips 34, 50, and 62.
The log shows read failed for temperature sensors on chip 62.
The firmware is trying a Special fix for the middle temperature, but it doesn't solve the loop.
What I've tried:
Re-ordered the hashboards, but the errors persist on the same chips.
The watchdog reports 0 hashrate across all 3 chains when the loop happens.
I'm about to start testing the hashboards individually to isolate the faulty one.
Question:
What could be causing these specific chips (34, 50, 62) to show NaN status? Is it a failed BM1387 chip "poisoning" the bus, or should I be looking at the LDOs/voltage domains?