Good question. A fixed voltage/freq probably isn't ideal here (I hadn't thought through that for this setup).

I'm relying on Braiins OS autotuning to step in and reduce hashrate if the chip temps start getting too hot. That could happen if my house's ambient temp gets too warm or if I dial back the external fan.

I've done the same with S9s w/external fans. I set a higher Braiins OS wattage target, but run a quieter, weaker fan in front of it. Braiins eeks out what hashrate it can, but modulates to stay under the target chip temps.

Have to manage it on that side since the control board has no control over the external fan.