Ok, so, the "30C" resistor is the 20k reference one.
"
and one of the
"123" resistor allows you to output 10.6v.
divided by 15 chips in a string = 0.71v at the chips
Edit:
not "123"(12k), but there should be a 1.2k resistor or close value.
1.1k resistor in place of the 1.2k will give 0.77v at the chips
1.3k resistor will give 0.65v at the chips
18k resistor in place of the 20k should also work for 0.64v at the chips
22k resistor in place of the 20k will give 0.77v at the chips
Edit, I'm aging, took me 20 minutes to figure the over/undervolt.
I am just working from the available pictures, but just to say that I agree with all of the above including the fact that I cannot find the approx 1.2K resistor which is needed from pin 2 on the LM27402 to ground as the bottom part of the potential divider?
I have a possible solution which is that U3 on the other side of the board, which in the pictures I cannot read the ident, is a Digital Pot, perhaps set up from the pads on the edge of the board, which would enable a value & hence the voltage to be set? Bit of a wild guess and could be for something completely different but easy to check if someone has a board out of a system.
Also uncertain about U2 marked AG30, is this an LDO & if so what is it for?
Also note that the Bitmain pictures show a V1 without U3 and that Batch 6 is V2 & Batch 8 a V3 Board
Rich
