You can use the firmware that I provide and remove 1 fan. The chips will stay hotter and then the outlet fan will still carry the heat fairly well. If you increase voltage temps will increase as long as freq is high enough. I recommend 8.9.
Thanks, yeah I found your thread helpful when it came to settings and using the fixed firmware, before bOS came out.
The more recent version of bOS is the only one that has allowed me to control both fans and frequency though. For me, Autotune firmware would let me control the fans, but obviously not the frequency. Fixed firmware would do the opposite, no matter what I tried. I went back and forth, manually added the settings, etc etc. The main thing for me, is getting the hot air into the room, so I wouldn't want less fans. I just run them at lower speed so they aren't too loud, keeping temps below 96C.
I manually adjusted my limits too, 96C for 100% fan and 100C critical. I'd love to change the fan from 100% though, since it's quite annoying and a waste of power to sometimes barely hit the limit, then go full throttle over and over until I bump the speed up a couple %, but I haven't found that setting yet. I'd prefer setting it maybe 5% more than my fixed fan speed. If that wouldn't do it, then frankly I want the thing shutting itself down. I know, I know, these aren't "home miners", but figuring out that setting would be golden for me.
Overclocking has nothing to do with that. If you want more "heating", simply add more miners. By overclocking, you are simply over-stressing the units, basically burning them out, so don't be surprised if they fail in the middle of winter...
If miners were free, then sure, but I don't have money to burn. The idea is to keep the costs less than the gas, by making use of what I have. At 11-12c p/kw electricity, S9s are no longer viable for me otherwise. I also used them that way last winter and they're still going fine. Well, minus the two boards that the early version of bOS killed, but that's another story. I've also overclocked my old KnC Neptunes in winter, and back when they were still profitable, for like 5 years now and they're still fine too. I'm finally starting to phase them out though, since S9s are getting cheaper, making it more cost effective. Obviously, overclocking does shorten the lifespan of electronics, but so far for me, the miners will be well beyond obsolete by the time I burn one out.
On the voltages, that's true, but in bOS, I've noticed that the lower you go in frequency, the higher the voltage it recommends, even going above the defaults. Of course the recommendations are just general guesses, but it has those guesses going backwards. So that might be confusing some people who don't know better. I agree, I haven't wanted to go above 9V either, but oddly bOS defaulted me to 9.1V on one board that always ran at 8.7, so I manually adjusted that one back down. It only did that after my over and underclocking though. Initially, it was 8.7V in bOS too. It's also my miracle board, aka the only one that didn't fry when the other two did.