Yeah, it works on I and J. I am not 100% about it working on the K so hold off on that I will confirm because otherwise you got to flash the board back to life and it's a major pain in the ass.
This is the instructions for the S9's
https://asic.to/documentation/Pardon the shitty language I have to rewrite it from scratch but I think I am going to re-write it for the S17 and T17 since the S9's are on their last leg.
There have been people that have gotten 2 s9's with 1 fan each running at 21th at 1500w off one psu. The autotune will be the saving grace for maximum efficiency.
Edit 4:
475 - 8.0 - 10 TH/s - 750 watt
550 - 8.2 - 11,6 ths - 950 watt
(78 waтт / THs)
631 - 8.3 - 13,5 ths - 1100 watt
(81 waтт / THs)
700 - 8.6 - 14,9 ths - 1300 watt
(85 waтт / THs)
750 - 8.7 - 16.1 ths - 1450 watt
(90 waтт / THs)
edit 5:
Although not nearly as efficient (or even BTC related) I just did something similar with an L3+
Just unplugged 2 boards (left the other 2 in) and it's a nice just about dead silent 250MH/s scrypt space heater.
Going to work on power and speed vs fanspeed and noise while playing with the number of boards but, it might be nice in the back room of the condo for the winter.
Makes you wonder how much gear we can keep running by doing this.
Going to play with an A721 next.
-Dave
now is that with stock firmware or are you making it worth a little harder or less through software?