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Fan is running at full.

Solution

Could replacing the fan actually fix the problem? Seems this is a problem is...

https://www.reddit.com/r/qnap/comments/khidso/possible_failed_main_board/

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https://www.youtube.com/watch?v=c5k8FWe6u60

Scope or measure the LPC-CN1(10-pin connector, next to 4-pin COM1 connector), pin 1 (LPC CLK, normal ~1.7V)
If the voltage is ~2.4V, solder 100 Ohm between pin 1 (LPC CLK) and ground (pin 8 or 10).
If the voltage is <1V, solder 100 Ohm to a 3.3V pin(since this does not apply to me, someone would have to spend time to find/test it).

Our issue:

Solder 100 ohm resister between CLK and GND

Image Added

References

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