Re: UNDER clock Antminer S9

I managed to underclock my autotune 13TH S9 by first upgrading the firmware to the 550MHz fixed frequency firmware.

Thereafter ssh into the miner. edit /config/bmminer.conf and change

Code:

"bitmain-freq" : "475",

Also one can change the directions of both the fans and the miner should reduce fan speed. Do not change the directions before underclocking though, as the miner will overheat.

I tried that on mine and both would go back to auto tuning the frequencies.

Did you successfully install the fixed frequency firmware first? One way to check is if your Miner Configuration page allows selection of "Search Frequency From" 550MHz.

Is that fixed frequency firmware new? As in within the last 2 months? I tried to make that change on the factory firmware (something from March 2017) and the august firmware.