Topic: Quiet Antminer S15? (Read 592 times)

Not the Asic fans, the PSU fans, if they are monitored/controlled its inside the PSU itself...


Its right here: Cybtc Review: Bitmain Antminer S15-28TH/s



It also looks like you can unscrew the grills:

That's been addressed already. There is a software that would allow me to bypass the fan control system. I could also fake the RPM signal. Or even easier, leave a fast turning fan with the fins plucked out strictly to report RPM.


Without testing, I am willing to bet a single 120 mm Gentle Typhoon fan spinning at 2150 RPM would push more air than the two small ones.


That idea might or might not work depending on how the PSU is configured.  What I am talking about is removing the two small fans and blocking that hole with tape. Than I would install a 120 mm or 140 mm fan on the side of the PSU, not on the front where the two fans are. To do this, I would have to drill holes on the side panel of the PSU. But again, I would have to see the inside of the PSU to know if this can work. It would be dumb to install a fan on the side of the PSU box that blows air onto the back of a board, basically cooling nothing at all.


I don't think you get it. I am proposing to double the number of fans at slower speed, which would result in the same air flow. And I would also remove the front grill for better air flow.

In my years water cooling we did all sorts of tests to find out what works best. Often times we found out that two fans on a radiator, one pushing, and one pulling, will yield better results at 1000 rpm than a single fan pushing at 2000 rpm.

So if that applies here, I should be able to double the number of fans while greatly slowing the RPM for either same or better air flow.

And other way to get better performance with less RPM is to use thicker fans. Bitmain got it right when they decided to use 38mm thick fans instead of the standard 25mm ones. A 38mm thick fan will push more air than a 25mm one at the same RPM.

I don't know if that PSU is monitoring the fans and needs to read rpm values, that would make things a bit trickier if you remove them, tho in principle i would agree. Bigger fans always moves more air making less noise at the same rpm.

I don't understand the "block the holes" part, that would be like removing them but leaving obstructions to the air flow.

You will want to run it in "enhanced low power mode" or if Braiins OS gets ported, underclock it.

From where I stand and without an actual machine I  front of me, there are two ways I can think of reducing the noise of the PSU fans.

1) Remove the grill on the exhaust side and add two exhaust fans. I'll put a fan speed controller on all of the PSU fans to determine how much slower I can get them to pull as much air as the two faster stock ones. If I can get them 2-3000 RPM slower, that should make a big difference.

2) Replace the two 50mm fans with a single 120 mm one on a shroud. Or maybe block the holes on the two small fans and install a 120 mm fan on the side of the case. Not sure about that  I don't know how the PSU is configured inside. That one might not be possible.

not to let you down, but anything aside from liquid cooling will not be quite enough to be placed right next to your pillow, we all have different sleeping abilities indeed, but for the average person, that's quite hard, i have been there, done that, never worked.

the box that phill suggest is a great idea, i used a slightly similar one before with a D3  "back in the glorious days", i made out of wood and tons of waterproof foam, i even used 2 ducts to further reduce the fan noise, the noise was reduced by a good amount, but never really quite enough for my wife not to nag all morning next day  . but as soon as i went out the room, the noise is totally gone. so if you got a spare room that will work, if not ! , good luck.

The psu high pitch noise cooling fans are the biggest issue with the S15.

Well, I'm coming up with a few more ideas to make it more quiet.

For instance if you replace the exhaust grill for a couple of fans you could probably get more air flow with 4 fans turning at 3000 or 4000 RPM instead of the two turning at 6000 RPM. And that alone would really help quiet down the rig. 3000 RPM fans are a bit noisy but far more pleasant than anything at 6000 RPM.

But maybe just a sound proof box will do. For now it's just speculations as I haven't got the rig yet.

And I'm not sure I'm going to need that software. Faking a fan RPM signal is pretty easy.

I'm very interested to see the results of your proposed modification, a quiet S15 could be very useful...
I agree that the grill is in the way, and its probably another source of noise.

If Braiins OS gets ported to it, a low power configuration would be very interesting to see, max efficiency usually also leads to quietness, when paired with underclocking.

Yup, hardware cooling is where I have some experience. As I stated earlier, rated CFM for fans is in open air with absolutely no restrictions. Once you add restrictions, you get a completely different actual CFM. Elbows in ducts, too narrow a duct, grills, filters...all contribute to slowing down the air flow. I think removing the grills on the exhaust side will not only help airflow, it will reduce noise a little bit as well.

it will be quite quiet with  a good box so pulling the small psu fans is not needed.  (at least until you can order a spare psu)  the psu is a specialty psu and spares are not searchable to get one. .

pulling the grill and adding an exhaust set of fans could be good idea.  also braiins os for the s15  will come soon which will allow for more fan control

braiins thread is here

https://bitcointalksearch.org/topic/braiins-os-braiins-os-custom-asic-firmware-optimize-performance-efficiency-5036844

Why not? If I can get just as much, and maybe even more airflow with my squirrel fan, why not?


I like your set up. So I am likely going to build something similar. I'll see if I need both the soundproof box and the fan replacement, or just one of the two.

I also think that grill on the exhaust side of the S15 is a complete waste. If you have no critters crawling around your farm, I don't see why those grills shouldn't be removed, or even replaced with exhaust fans.

I think 4 fans spinning at 4000 rpm would move more air than just the 2 fans at 6000 rpm.

Thanx for the video. Now I'm 100% confident I can make the set up a lot less noisy.

dude  do not touch  the stock fans

build a box.

the s15 can easily   work in a box  like the one I built

https://www.youtube.com/watch?v=auakWENgP8w

notice it fires into  a cushion  placed 2 feet away


this one the sound meters more accurate

https://www.youtube.com/watch?v=P8MwWwctWVw


I can tell you that box has run

avalon a721
avalon a841
avalon a921

whatsminer m3
whatsminer m10

s9
s15

dragonminer t1
inno t2turbo

and the s15  is pretty good inside it.

my channel does show  how that box was built and other gear in it

https://www.youtube.com/channel/UC-K1Sokgy3-4CdV_uZF8ubw/videos?shelf_id=1&view=0&sort=dd


I constantly test  new gear in it

I can say the s15 works well enough that I can not tell if it is running when I sleep directly above it.

the quietest was a downclocked avalon 841  but it uses  90 watts a th

the s15 is about 56 watts a th on an asic pool like ckpool or viabtc.  high speed.

Okay. So here is my squirrel fan:
 https://www.amazon.com/Vortex-Powerfans-VTX600-Powerfan-Inch/dp/B001JKYTLG?th=1&psc=1
I don't remember if mine is the 6" or 8" model, I'd have to dig it up and find out.
497cfm for the 6" one and 739cfm for the 8" one.

And here is a replacement fan for the stock ones:
https://www.amazon.com/fosa-Replacement-Connector-Antminer-Inverter/dp/B07CHGP1VF/ref=mp_s_a_1_11?ie=UTF8&qid=1549504338&sr=8-11&pi=AC_SX236_SY340_QL65&keywords=antminer+s9+fan&dpPl=1&dpID=51-T1VmNHuL&ref=plSrch
6000rpm, and a claimed 210cfm.
Mind you, we really should take that cfm rating with a large grain of salt. In a crammed box with a lot of restrictions, that's going to drastically decrease the actual cfm.
What matters most with fans is the static pressure and very very few manufacturers bother to list that in their specs.

So either with the 6" or 8" Vortex fan, I am still ahead of the stock fans if you go on cfm rating alone. And the Vortex inline fans are known for their high static pressure. I think I'll be just fine.

If you replace the fan I think the controller will not recognize it you must replace it with compatible one or you can just bypass it.
There is a tool to bypass the fan detection like this one "555 timer circuit" they mostly use it to bypass the fan detection in s9 but I don't know if it will work on s15.

Could well be that they are 38mm thick and that number stuck out 

Point well taken, thank you.
I have no idea where I got that 38cfm figure.
I have some Gentle Typhoon fans right here with 2150 RPM and a rating of 68 cfm. So that 38 cfm at 5-6000 rpm is obviously wrong.

Another thing I could do is just replace the stock fans with slower ones. I got some top shelf 2150 rpm 84 cfm fans that are completely silent.  I could use a couple of those supplemented with the squirrel fan. That should work.

Are you sure the standard fans are 38cfm?

I'm only saying as I have just hooked up a Noctua 92mm fan to my Gekko USB Hub and that has a rating of 37.8cfm.

Here is a link for replacement fans from a known mining gear supplier:-

https://www.parallelminer.com/product/antminer-s9-s9i-fan-fan-replacement-38mm-4500-rpm-186-cfm/

Those are ridiculously tiny fans. I'm sure I can design a shroud to accommodate all the 120 mm fans and these two pimples they call fans.
In any case, desktop PSU's I have worked with don't usually produce a lot of heat. So I'm sure these would be easy to silence.

I think I would design a single shroud that pretty much covers the whole back side (or intake side) of the miner. And just obstruct or widen the holes to increase or decrease airflow accordingly.

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I'll see if I can draw up a doodle of what I have in mind.

My plan is to build just a wooden box. With no sound proofing. And if I see that sound proofing is indeed needed,  I can always add layers of it on the outside of the box.

Both the squirrel fan and the S15 will be suspended inside the box with bungee cords to eliminate vibrations.

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Here is a rough doodle of what I have in mind.



The dotted line in the intake will be a bug screen. The orange squiggles will be an HVAC dust filter to keep the dust out. If this proves to be noisy, I will add soundproofing on the exterior of the box.

You can see the fans in the above picture, they are quite tiny but I dont know exact measurements or specs as I have never seen a PSU spec sheet for these models.

If you go this route I would like to see pictures of your resulting box. I think any wooden box covered in sound insulating fabric inside, with input and output holes, attached to a small section of sound insulating duct on both sides should work. Perhaps for the S15 you'll need two 6" holes instead of one on each side?

See philipma1957's quality craftsmanship and how nicely reduced the noise to his S15



Perhaps this 6" circular hole nonsense is overrated, and all you need is two big square holes on the extremes perpendicular so the air flow does a 90° turn (to deflect noise).