Bitcoin Forum

Hey guys.
New guy on the block here, first post.

I'm thinking of getting back into mining. I did it for a few weeks back in 2009 when Bitcoin first started. Got me 10$ worth when it was about 10 coins per penny.

So anyways, the scene has changed a great deal in 10 years.

I 'm thinking of buying an Antminer S15. But I live in an apartment complex. And the machine would have to be in my bedroom. I'm thinking that 76 dB is just too loud (vacuum cleaner loud). So I came up with a few different ideas on how I could go about making it more quiet.
I just want to bounce those ideas off of you guys just to make sure I'm not completely out of my mind.

1) Water cooling.
I do have a lot of equipment and experience in computer water cooling. But I would have to design and build my own custom water blocks for the S15. And that would be prohibitively expensive.

2) Mineral oil submersion.
I have seen some people online who submerge their entire computer in mineral oil. I have no experience at all in that. And it would be expensive for me to go that way. My rads and pumps are just not built to handle something as thick as oil.

3) Replace the fans for a squirrel inline fan.
The two fans that come with the S15 are 120 mm fans turning at 5-6000rpm for a meager 38cfm of air. I have an 8 inch squirrel fan that pushes 630cfm of air in almost complete silence. So I was thinking of removing the two stock fans and installing the 8 inch fan with some sort of duct on it to plug to the S15.

The whole set up with be in a sound proof box installed in the window for intake and exhaust to the outside.  

I'm thinking that this fan would push a great deal more air than the two 120 mm fans. And so I might even be able to OC the S15 for a but more juice.

Does this sound crazy? You guys think it makes sense?

The controller would need to see an rpm signal from somewhere within its specs otherwise it wont hash.

Why don't you go with option 1 which is where you have the experience? There are after market solutions for the S9, I'm sure the same (Chinese) sources will put out aftermarket water cooling kits for the S15.

Did you take into account the maintenance hassle that involves mineral oil? There is another dielectric liquid used for refrigeration, cleaner like water but expensive:

https://http2.mlstatic.com/fluido-refrigerante-dielectrico-para-antminer-y-pc-D_NQ_NP_758577-MLV27401265112_052018-F.jpg (https://http2.mlstatic.com/fluido-refrigerante-dielectrico-para-antminer-y-pc-D_NQ_NP_758577-MLV27401265112_052018-F.jpg)

Option 3 sounds interesting as well, maybe with some 3d printed adapter?

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Any cheap case/cpu fan would happily report rpms, you can even remove the blades, and you don't need the fourth control wire either.

I can fake a PWM signal. Or as already pointed out, I could chop off the blades and let the fan spin purely for RPM signal.

So this is a good idea if you want to feel like you are a part of the bitcoin network, but just know all the added costs of quieting the miner means your chances of ever even breaking even are pretty poor

I just would love to water cool it. As I know I would be able to render it silent, I already have enough rads to do that. But I have been unable to locate a source for water block. And the only block I was able to find for an S9 is aluminum. That would be a complete waste of money. I would only use copper blocks. Never put aluminum in a water loop.

I would invest the time and money into designing and producing a water block for the S15 if I knew there would be others interested in buying some blocks to offset the cost. But the useful life of a miner is 2 years at most. Not sure there would be a market there. I'm pretty sure I would have to pay at least 1000$ for a prototype to be made.

I can see computer guys water cooling because it's more of a hobby to them. But miners have profit in mind more than the hobby or cool factor. Not too many miners would justify paying upwards of 4-500$ for a water cooling system.


I only briefly looked into mineral oil. It would be interesting if I could use my water rads/pumps/stuff for it. But I think  oil would be too viscous for water rads and water pumps.


Please tell me more.


I have access to an English wheel and a metal shop. So the shroud or adapter wouldn't be too hard to figure out.

The stock fans I believe are rated at around 38 cfm at max speed. But those ratings are usually in open air without restrictions. Once you add some restrictions like the inside of a miner, or a rad, or a dust filter, that rating goes way down. The squirrel fan I have and would use as replacement has a rating of 630 cfm at full speed and much higher pressure too. So it wouldn't be affected by restrictions as much.

I'm thinking the added cooling of such a fan would allow me to OC a bit. But I would be happy if all I can do is run stock clock quietly.

But I am curious as to how much of the fan noise on the stock S15 is from the actual fan, and how much is from the air rushing around in and out of the miner. Pushing air through a bunch of heat sinks inside a miner is going to make some noise. I'm just not sure how much.


Exactly my thoughts. It wouldn't be too hard to fake a fan rpm signal. And even easier to just trim off the fan blades and allow the fan purely as rpm reporter.


In my specific case, water cooling wouldn't be expensive at all as I already have everything, spare the water block. That one would be pricey. And I don't think I could offset the cost with selling a few blocks to other guys. It wouldn't be much of a market from where I stand.

The 3rd option would also be pretty cheap for me  if it works. I already have the fan. I just would need a few hours of labor to make the shroud/adapter.

Also I am in an apartment complex with free power as part of the rent. So if I only have one or two miners, nobody else will notice the small hike in power usage. I share the power meter with an other 24 units.

Just as an FYI its the PSU fans that really make these units noisy, it is a grating high pitch whine

Option 2 would be a nice option but the problem it can void the warranty of the miner unless if you are fine without warranty.

Why not adding this option "noise reduction box"?

https://i.ebayimg.com/images/g/0-sAAOSwXtNaeCFZ/s-l300.jpg (https://i.ebayimg.com/images/g/0-sAAOSwXtNaeCFZ/s-l300.jpg)

You can make your own customize design but this time you need to make a 2 holes on the front and back of the box for intake air and exhaust air.

I'm not sure it would work on s15 miner but it can reduce the noise of s9 miner around 40%.

As I understand it the S15 only has two intake 120 mm fans on it, does it not?

Maybe one of them is for the PSU. Never the less, the one squirrel fan  would replace both of them with a rating of 630 cfm versus 2x 38 cfm and way more static pressure too.


Yes, I do plan on building a sound proof box. It would be hanging out of the window. So it would take fresh outside air and exhaust to the outside. Or maybe exhaust to inside in winter. Here we get rather cold winters down to -25C. So not sure if the air would be too cold for the electronics. If so I would just slow the fan speed way down.

What did you use for sound proofing material?

Take a look at the unit. There are 2 120mm fans to cool the hashing boards, but the PSU is built in with 2 small fans as well. Small fans spin at very high RPMs to move enough air to cool the PSU, which makes them very noisy.

Yeah, small fast fans are annoying. But I don't have anything I can look at in person, only pics from the net.
Where are the PSU fans located? What size?  60mm, or 100 mm fans? Do you have an idea of their approx. RPM?
I hope I would be able to build a shroud that could supply some of the squirrel fan air to both the boards and the PSU.

From the start, I was afraid that the PSU might be a source of noise, I just wasn't sure how much.
So that might kind of takes the water cooling option off the table. If I have to design a water block for both the hash boards and the PSU, it's getting too pricey and too complicated.

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 (https://bitcointalk.org/index.php?action=profile;u=64507)'s quality craftsmanship and how nicely reduced the noise to his S15 :D

https://i.ibb.co/5GLsKdT/image.png https://i.ibb.co/LxQ1tLZ/image.png (https://youtu.be/P8MwWwctWVw?t=63)

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).

https://res.cloudinary.com/dluwgr5op/image/upload/c_fit,f_auto,h_450,w_750/v1541664514/wwobtuq2mpqkialy4ewt.png (https://res.cloudinary.com/dluwgr5op/image/upload/c_fit,f_auto,h_450,w_750/v1541664514/wwobtuq2mpqkialy4ewt.png)

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.

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.

https://i.ibb.co/CB2HSFy/20190206-134851.jpg

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.

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/

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.

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

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 (https://www.electronics-tutorials.ws/waveforms/555_timer.html)" they mostly use it to bypass the fan detection in s9 but I don't know if it will work on s15.

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.

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.

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.

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://bitcointalk.org/index.php?topic=5036844.0

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.

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.

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.

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

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  ;D. 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.

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.

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.

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.

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 (http://www.cybtc.org/article-137-1.html)

http://www.cybtc.org/data/attachment/portal/201901/29/142404trrdjb1jdzf49xhk.jpg (http://www.cybtc.org/data/attachment/portal/201901/29/142404trrdjb1jdzf49xhk.jpg) http://www.cybtc.org/data/attachment/portal/201901/29/142403fk4t64k44gvbg6o3.jpg (http://www.cybtc.org/data/attachment/portal/201901/29/142403fk4t64k44gvbg6o3.jpg)

It also looks like you can unscrew the grills:

http://www.cybtc.org/data/attachment/portal/201901/29/142356tuvp0vcqpc0lqvvq.jpg (http://www.cybtc.org/data/attachment/portal/201901/29/142356tuvp0vcqpc0lqvvq.jpg) http://www.cybtc.org/data/attachment/portal/201901/29/142407p8wynsnsl0xlmwyw.jpg (http://www.cybtc.org/data/attachment/portal/201901/29/142407p8wynsnsl0xlmwyw.jpg)