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Lionel Coin Bank | 11 months ago (raw) | root | parent | reply | flag 
 How are the fans controlled in this setup? Are the default S19 fans still on and connected?
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KeithMukai | 11 months ago (raw) | root | parent | reply | flag 
 The 4 case fans (2 front, 2 back) have been removed. The 6" inline fan is doing all the work. It has a manual speed dial which I have been tweaking while Braiins OS autotunes. Trying to keep the chip temps below 75°C.

A little disappointing, but basically having to run the fan at full power to keep up, so a little noisier than I'd like (~59dB @ 1m). But still way better than the high-pitched case fans.

The S9 power supply (APW3++) has its own small fan, but it doesn't contribute anything audible when the 6" is pushing this hard.
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Lionel Coin Bank | 11 months ago (raw) | root | parent | reply | flag +1 
 Thanks for the reply sir! Been a fan of your work for a long time.

So your long term plan is to auto tune and set a specific hash-board voltage and then have the fan running at a constant rate unless manually adjusted? And if board temps ever get too high for that constant cooling rate, will the S19 automatically throttle?
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KeithMukai | 11 months ago (raw) | root | parent | reply | flag 
 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.