I am starting to learn how to fix these boards, hope this is the right subforum

I'm hoping someone can give me a pointer where to look next. I feel like something is messed up with a 1V8 line *somewhere* but I can't really pinpoint it.

Symptoms (Hashboard 63 V1.9) :

Board is not detected - I believe the kernel log showed "can't find sensors" and it hangs there.
I measure .772 V to the base of Q86 (The 1V8 -> 3V3 level shift transistor for RX)
This is ~1.7 V on a good board.
Audible clicking from the power supply section. (Assuming one of the switching supplies - but don't know which.) Both 14V (14.32) and 9V (9.2 V) appear.
Makes me believe something is loading a supply somewhere.
I am reading .464 V on the RI testpoint near IC 2. (The third one in the chain - on what I believe is the 1st voltage domain).
IC Good Bad
0 1.6 V 0 V
1 1.6 V 0 V
2 2 V .464 V

Does this pinpoint IC 0 & 1 as dead? When I compare RI resistance to ground I get roughly 200k on both good and bad.

Side question: Where the heck is 2V5 generated?

thanks for any nudge in the correct direction

IC	Good	Bad
0	1.6 V	0 V
1	1.6 V	0 V
2	2 V	.464 V

dext0rb

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