Ideas for s9s and broken temp sensors

I've been tinkering with my 28 different S9 models, including the S9, S9i, S9j, and S9k. I was thinking about turning 1 or 2 of them into space heaters. So far, I’ve managed to create one space heater out of a single board and five heaters using two boards. I've come up with a bunch of hacks over the last few days. One is using Braiins+. I found it’s easiest to underclock these machines. I used an SD card for this. First hack: I noticed that the SD card slot is sometimes upside down on certain S9s, so if your SD card isn’t fitting, just flip it over and it might work. Second hack involves the jumper that allows the SD card to boot. There’s a tiny plastic piece with a smaller metal connector inside. Just make sure when you pull the jumper, you don’t lose that little metal bridge. Third, about those temp sensor chips on the boards. If they're reading zero, they’re dead, and both Bitmain and Braiins will run the fans at full speed, which makes creating a quiet space heater pretty much impossible. I’ve got nine boards that do this, and they all crank the fans up to max. So what's the fix? Since these builds are all about low noise and underclocking, you’ll want slow RPM fans that only go up to around 1500 or 1600 RPM at full speed. Load the S9 with three subpar boards and clock the volts to 8.1, set the frequency to 250, and fan speed to 90%. The miner will run at 90%, then jump to 100%, but since your fans are low-speed, you'll end up with a pretty quiet three-board space heater. I’ll share some screenshots and photos later.

spacing. So I realized that chip reading at 0 or dead chip means these boards will cause 100% fan speed. So for all practical purposes you don't need a 4 wire fan for ppm control. I put in 2 corsair 3 pin fans that top out near 1400 rpm they are set to 90% speed and the braiins software will eventuallyy sense no chip temps and then max the fan speed out. Since I am clocking low and attempting to have a space heater with defective heat sensor I must keep an eye on the board sensors.

spacing. They have been running for 2 days they use 402 watts around 4.4 th or about 91 watts a th they are silly quiet .

If you decide to try autotune, remember these two parameters: Powerlimit, and Target Temp. By default target temp is intentionally 89°, this probably makes the fans go even slower if left alone, but you can lower it if you want. And powerlimit indirectly tells it how much power it can use, and thus not exceed a certain speed voltage combination. With autotune, bosminer+ controls chip speeds individually. You should wait until it shows "stable" before measuring power and noise. Good luck! Autotune may let a few errors if it considers the hashrate to be more efficient even with some, so don't worry too much if you do see some, as long as the resulting hashrate / watt use is good. People have achieved even 69W/T so you should aim for something at least in the 70ies, 91 feels a bit too high... Oh but i guess you need 240v and not exceed 80% PSU capacity.

Hmm I have switched out fans  and the psu's can do 1200 on 240 and 900 or 120 but with 2 boards I should set 300 watts and see what happens.

Oh i forgot to mention something. This is not obvious, but always treat the powerlimit as if there were 3 boards. It doesn't matter if there are only two or one, it doesn't literally share the amount you input to the physical existing boards, but will try to give a third of it to each, even if there is only one. But let it run at 300w just for fun (and science). I think some people had good results at 600w, another at 800w. Since you are limited to 900w, perhaps no more than 720w would be good.

I have a programmed controller but i think i did braiins and not brains + as it is not allowing every option.

You can change back and forth from Braiins OS into Braiins OS+ and back. Relevant ssh command and instructions: Switch to Braiins OS+ from other versions using OPKG Switch to Braiins OS (without autotuning) from other versions using Sysupgrade To move from Braiins OS into Braiins OS+ you just need to install the package bos_plus which can be done from the web ui as well. In the version number at the bottom of every page it says when its plus or not, also the graphic in the upper left corner of the web UI.

You know I was thinking about your heater idea and it came to me, why not make it a heater & air purifier! On the intake add a activated carbon pads(they look like green scrub pads but black and usually bigger) and maybe even a paper filter, one for a lawnmower should do not hepa grade but will get the small stuff. This idea may require some custom fabrication to hold the filters. Not sure how the fans would handle it. But its an idea. Thought I throw it out there. I ran across this post and now have a one board going myself Hopefully soon get solar implemented once I have all the pieces.

has some promise I just got new s9 drop in kit from a builder I can do 1  2 or 3 boards 3 boards on low give me 16 th and 900 watts  this is about 56-57 watts a th 2 boards on low give me 11 th and 616 watts  this is about 56-57 watts a th I am thinking of making improved low power miners. using the s9 shell and s9 fans and s9 controllers and of course drop in these new boards.

Those are some really impressive numbers! I bought my first s9 13.5 a week or so ago and loaded up braiins+. Im strapped on how much power i can use here so I opted to run one board. The auto tuning process has it at 7.94v/ 617MHz/ 4.4Th/s @ 383 approx. watts total. Keeps my shed warm, and may pay for my sons schooling if I get lucky over at ckpool

right now I am doing 8.2 th at 463 watts 2 boards. I could do 4.1 th at 240 watts 1 board.

locking this it will move downward. in step with the older thread.