what is the relationship between frequency and voltage? Also how directly does it relate to the power consumption? I tried to find information about such things but the web has too many documents discussing other stuff but using these words so search engines are net helpful. Would be really grateful for some hints / pointers or explaination as I am obviously trying to find a sweetspot of low enegery consumption and less noise fan speed.

I have not been able to underclock my T9+ with the supposed settings that were suggested here but playing around with the ideas from here I found a solution that I wanted to post / share.

So the problem was that that my miner also already had autotuning available and changing "bitmain-freq": "some_value" would be ignored after rebooting.

So first I recognized using top that there was a process /usr/bin/bmminer --version-file /usr/bin/compile_time --api-listen --default-config /config/bmminer.conf running.

Thus I checked /usr/bin/bmminer --help to recognize that there is an option --fixed-freq        Set bitmain miner use fixed freq which probably could also be set in /config/bmminer.conf.

Thus I added the line "fixed-freq":true, to the bmminer.conf so that in total it looked like that:


In this way I was able to underclock the miner and tune down the fan. actually the PSU is now more noise as it's fan cannot be regulated by the software (what a pitty because it still produces 50db).

running the following firmware: