Antminer S5 + Laser cutter mods...

[MarkAz]

First off, I'm a big fan of what Vorta has been doing on his thread - if you haven't checked it out, definitely go there and check it out:

https://bitcointalk.org/index.php?topic=1072176.0

I've been experimenting a fair bit with different case designs as well - in particular trying to find the best balance of cooling + sound + ease of build.  As Vorta mentions, the thermal sensor on the blades is really a poor design - it doesn't really give you a good sense of what the board is actually doing, as I've I've seen it report 70c when it reality it was 90c+.  I have a thermal camera (BTW, you can mod the E4 to have all the features of the E8, awesome!) that I've been using to analyse the heat dissipation and what is actual happening to the boards as I change things around - and try to use things less subjective, like anemometer to measure actual airflow, etc.



It's important to note on the thermal side of things it's a bit tricky measuring it - because things like acrylic are not thermally transparent, so they need to be removed in order to measure temperatures.  At the same time, this affects the airflow, so in general I try to let it run for a couple minutes assembled, then pop off the side or whatever and image it so I get something that's closer to what reality is.

The first thing I did was replace the sides - personally I like the look of the circuit boards, so transparent acrylic works well for it in this case.  I was also bored and decided to etch a BTC logo in it to be fancy:



I went through several design iterations, but ended up with this as the best general configuration - the sides are 2mm acrylic and the top and bottom are 5.6mm, but only because I used up all my 2mm and only had 5.6mm left.  I think 2mm all around is what I'll use for my finished version.  I also took the hint from Vorta's on ducting, and put a 5.6mm spacer between the fan and the enclosure - this actually made a big difference no matter what you're doing, so if you're looking for a super simple mod to do - do this.  Here's the assembled verison:



It's worth pointing out the only the sides and bottom are screwed in - the top just rests on the PCB and sides.  I found this to be the most convenient, and the cables and everything else hold it in place really well, so there really isn't a big need for anything else.  You can see here how it attaches to the bottom:



Vorta filled in the bottom area with his design - which I think is technically better, but most of the fins on the bottom of the heatsink on my S5's look like a dogs lunch, so this works in all situations, and gets the bulk of the gains.  You can see here a closeup on the top, and how it's edged around the Beaglebone:



In some of my earlier designs, I basically screwed into the top much like I did on the bottom of the heatsink, and then made my own mounting adapter for the Beaglebone - but this didn't make any difference in my measured results, and was actually a huge PIA to install - whereas this one just drops on and you're good to go.

Now, the only thing better than not generating heat is getting it the F away from whatever is making it, so ducting is also a big consideration for me - here was one of my first experiments with this design and a 4" duct:



Unfortunately, a 4" duct doesn't allow a large enough volume of air through, so it hurts the thermal performance too much for my tastes.  I'm in the process of changing the flange that connects to the case, and moving up to the larger 6" ducts common to HVAC.  I know I could have gone to 5", but in the US at least they are hard to find at Lowes or Home Depot, so better to have too much air volume than too little.

Once I was happy with the general design, I started playing with fan configurations - push, push/pull, and just pull.  While I love the performance of the stock fan, I don't like the sound level - I've literally bought every 120mm fan that Amazon has to offer, and I've settled on this one:

http://amzn.to/1S6nDAV

I've probably bought about 50+ in the past few weeks, so they're probably wondering what's going on!    It doesn't have nearly the performance that the stock fan does, but it has the best balance of the ones I've used.  One downside is that it's not PWM controlled, but it's fixed speed of around 3k is more than acceptable for my purposes, since all my S5's ever do is spin up to full speed anyway - and personally I'd rather have the fan fully working the whole time anyway.  Back to the case, without the enclosure, push is definitely the way to go - with there being a slight advantage to push/pull, but generally not worth the extra cost IMO.  But, with the enclosure, pull works significantly better, and push/pull gains even less than the non-enclosure situation.  Now, keep in mind, I'm basing this off my thermal readings of the PCB, not the temp reported - although in general they tell the same story.  So here's one of them in action:



I think I may do a couple more minor tweaks, but I'm pretty happy with this design, and I'm more than likely going to do a big batch of them so I can upgrade all my existing cases.  I wish I had one of the new S5's with the heatsinks on the side to test with, but even though I've bought a ton of S5's in the last month, I haven't been able to score one with them.

If anyone has any suggestions or ideas, I'd love to hear them... Since I'm in the mode of still tweaking it, now's the time!

And if there's enough interest, then I may make them for other people when I do my big batch - one nice thing is it's super easy to do, you can install it in under 5 mins and it's good to go.

[1715443886]

1715443886

[notlist3d]

Very nicely done!  I love the clear of still being able to see the circuit boards. 

Another very well done mod!

[pinhead666]

Nice.This is how I like it: simple,cheap and does the job. Vorta's design is cool but for me it's little too HIFI.Well done  .

[AtomicStrike]

Good idea, because heat dissipation is bad on this models.

[Vorta]

Very nice indeed! Good work with all that! I see you also took the Scythe Ultra Kaze fans. They really are the best choice.

What I would suggest is try getting some mini heatsinks to glue them on the outside and see if that drops the temps. In your case they should drop them more than they do in open case versions. On my first miner, which came without external heatsinks, I used these: www.ebay.com/itm/171764372281. Glued them on with this thermal adhesive: http://www.ebay.com/itm/111172816819
I got a price of $30.00 for 60 heatsinks, so if you're buying them, make sure you click "Make offer" instead of just buying them at stated price.

I would definitely prefer to have acrylic side panels on my miners. You have me a very nice idea.

[MarkAz]

Hey Vorta, thanks for the heads up on the heat sinks - I was searching around for something good like that, but hadn't found anything close with nice big fins like that.  I just submitted an offer, so we'll see how it goes - I'd love to update all my S5's to use then, but first I'll see how much of a PIA doing one of them is. 

One thing I was wondering about was the placement - if you see on the image with my thermal camera, those heat dissipation squares on the PCB are actually fairly cool, it's the surrounding area that really heats up.  Here's a closeup  of that area on one of the newer PCB's (the one in the test case is an older S5):



The actual thermal squares are running a cool 105-115f range, whereas the area immediately surrounding it is in the 160-180f.  I'll be interested to see what kinds of difference they make - I'll try some with just thermal paste first and see what they do.  I can't tell if those regions are cooler because they're more effective at dissipating the heat (I'd be surprised if it were that pronounced), or if there were a heat sink there if it would absorb and radiate some of that surrounding heat.

With your ducts, did you play around at all with sizing the ports that you're using to the sides?  I know you have one with and one without the sides, but just wondering if you played with larger vs smaller openings.  Also, did you play around with different lengths?  Mine is 5.6mm but only because that's the thickest material I had around - I could easily just use multiple ones to get more length, but wasn't sure if the gain between 5.6 and 25mm would be worth it (I read somewhere that you reached peak duct performance at 25mm for case fans, but who knows). 

[valkir]

Nice I like the heat view! 

Great job.

Could you give us a screenshot of the hashrate and temp with and without the acrylic?

[spazzdla]

I really like that clear case design!! 

I like the S1 as the boards are open.  THe s3 is awesome and all but I like the rugged look of the S1.

[Crypto84]

MarkAz, do you by any chance have schematics of this? i have access to a laser cutter and would like to use your design. if not, all good. just thought i'd ask.

[OgNasty]

I also took the hint from Vorta's on ducting, and put a 5.6mm spacer between the fan and the enclosure - this actually made a big difference no matter what you're doing, so if you're looking for a super simple mod to do - do this.  Here's the assembled verison:

Can you talk a little bit about the advantages of this?  Will you be selling parts to do these mods?

[MarkAz]

Vorta mentioned the ducting benefit on his thread, and I was familiar with it from the PC modding side of things - but basically if you put some clean flowing air between the fan and the device, you can get better efficiency.  For example, currently there are the two pillars (from the head sinks) that split the intake into effectively 3 parts - when the fan is pushing or pulling air against this, it's less effective because it's so close - less opportunity to allow adjacent air to flow around it.  This isn't technically the most accurate way to describe it, but it gets the idea across - so by adding a clean space for the air to move through, it can more easily move around those obstacles would undo turbulence.   In practical terms, if you just throw even one of my 5.6mm spacers inbetween the stock fan and the case, you'll see about a 2c drop in indicated temperature.  But once again I have to stress, the indicated temperature isn't worth a whole lot, but it is interesting.

The reason I did it was more because my pull fan would hit the screws on the back of the case, so I wanted some spacing.  I believe what I've read is that around 1 inch (for case fans) is ideal length, anything more doesn't buy you anything - but I was surprised to see such a small space made such a big difference.

As far as selling parts, when it's all said and done, if there's enough interest than I probably will... For small guys, it's a super easy mod to do, totally reversible so you can undo it if you don't like it, and it makes for a much more house-friendly S5.  For the bigger boys, I think the ducted solution will be awesome, as my hope is to eliminate the need for any fans at all on the S5's, and instead have a plenum and single large fan.  I've seen similar configurations before in manufacturing, and I spoke to an HVAC designer I know and he confirmed that it should be doable.  Greater reliability, and massive noise reduction - plus depending on how large a deployment you're doing, it probably could even save a couple amps when it's all said and done. 

One other maintenance plus of this design over the push design is that the heat sinks are exposed on the front, and if you've ever taken a fan off of an S5 that's been running for a while, all kinds of junk builds up behind the fan - and this really affects the cooling.  With the pull design, that's not something you need to worry about because it's obvious when buildup happens.

[alh]

I also took the hint from Vorta's on ducting, and put a 5.6mm spacer between the fan and the enclosure - this actually made a big difference no matter what you're doing, so if you're looking for a super simple mod to do - do this.  Here's the assembled verison:

Can you talk a little bit about the advantages of this?  Will you be selling parts to do these mods?

There was previous S5 fan noise thread quite a while back. One member mentioned that he used a dead 120mm fan as a "spacer" between the regular S5 fan and the metal plate of the S5. . He cut out the motor, blades, motor support, and just retained the 120mm shroud of the fan. He noticed a reduction in noise just using the stock fan. While it looked almost like two fans stacked at the one end, it supposedly worked well at reducing the noise.

This was essentially the spacer mentioned above, and about 25mm "thick". I think the idea is that the air flow is a bit more "organized" by the time it actually hits the heatsink. That's my simplistic understanding.

[Rabinovitch]

I don't want to say about aesthetics, it's a matter of taste, but this mod is good for cooling. 

Why don't you stick a little radiators to those S5s on which this is possible, like on this:

[MarkAz]

I don't want to say about aesthetics, it's a matter of taste, but this mod is good for cooling. 

Why don't you stick a little radiators to those S5s on which this is possible, like on this:

The nice thing about acrylic is that it's in pretty much every color, so instead of clear, it could be black or whatever else - it really doesn't matter.  Opaque black would look very much like the older miner...  I'm with you on taste - and I'm not saying I made some piece of art, I'm just saying I prefer this look over the flimsy black plastic sides - they make an otherwise solid device feel a bit cheap IMO.

As far as heat sinks, I ordered some up, but I'm going to experiment with where I place them as the thermal image shows heat dispersion that's different than I would have expected.

And that idea of hacking a fan for a duct - I saw that also, and actually bought these to test it out:

http://amzn.to/1HxzCoi

It's pretty much the cheapest 120mm on Amazon (basically $4 each prime)... I can't speak to the quality of the fans, but the enclosure works well.  I didn't see much difference between my cut spacers and these, so I just stuck with the ones I made - but if you want a quick and easy way to do them yourself, this way definitely works.

[valkir]

That really nice. I did try yesterday to put the S3 cover on a S5 and was surprise to realise that this doesnt work since the fan plug are on the top and block the cover and because the hole are not at the same place. 

[NotFuzzyWarm]

Very very nice!
Only thing I would suggest changing is that for fire safety, use polycarbonate (Lexan) vs acrylic. Acrylic does not self-extinguish whereas polycarb does.
Only problem though is esthetics as polycarb gives a bit bubbly & brown edge when laser cut.

[MarkAz]

Very very nice!
Only thing I would suggest changing is that for fire safety, use polycarbonate (Lexan) vs acrylic. Acrylic does not self-extinguish whereas polycarb does.
Only problem though is esthetics as polycarb gives a bit bubbly & brown edge when laser cut.

From an aesthetics standpoint, I actually think that laser cut Lexan looks cool - I've done it a couple times, but nothing large.

The problem with Lexan is that it outgasses some nasty stuff that ends up damaging the laser - that's why most places won't laser cut it - only places with rocking air extraction (and while I do have outdoor power venting, I do not have air extraction). In all of my temperature tracking on both the PSU's and the miners, I don't think I've seen them exceed 200f at the point of heat generation.  Now, that is right at the bottom temp that acrylic will start to soften but the melt point is north of 300f, so it shouldn't be an issue.  Plus even at the screw to heat sink points (at the bottom of the case), and where I would expect to see the highest direct temps, about the max I'm seeing is 115f.  The big advantage is the airflow does a good job of keeping the acrylic cool...

If you have any other material suggestions, let me know!  I was more concerned about the temperature issues on the PSU's, as the definitely hit higher temps - and I was looking for a thin material I could use as a buffer layer, but hadn't found anything that was super cost effective yet.

[MarkAz]

I've been buying a bunch of used S5's lately, and once I get and test them, I'm converting them over to my case - and this is a prime example of why I prefer pull vs push fans (warning, graphic imagery):



With pull, you always have buildup behind the fan, which works as basically insulation... That's not to say that pull isn't without it's issues, you basically have buildup where the air comes into the case.  The difference is that with pull its usually very easy to see and clean up - whereas pull is just sort of lurking behind the scenes.

Anyway, I'm in the process of converting most if not all of my machines to the 2mm version, and we'll see what kind of difference that makes overall in airflow with my boxes.  Unfortunately I've also up in forced air at the same time, so I can't really compare apples to apples, but I think the ability to focus the exhaust air in one basic direction is going to be great.

[Vorta]

Hey Vorta, thanks for the heads up on the heat sinks - I was searching around for something good like that, but hadn't found anything close with nice big fins like that.  I just submitted an offer, so we'll see how it goes - I'd love to update all my S5's to use then, but first I'll see how much of a PIA doing one of them is. 

One thing I was wondering about was the placement - if you see on the image with my thermal camera, those heat dissipation squares on the PCB are actually fairly cool, it's the surrounding area that really heats up.  Here's a closeup  of that area on one of the newer PCB's (the one in the test case is an older S5):

http://www.analogx.com/images/laserS5v1/flir0069.jpg

The actual thermal squares are running a cool 105-115f range, whereas the area immediately surrounding it is in the 160-180f.  I'll be interested to see what kinds of difference they make - I'll try some with just thermal paste first and see what they do.  I can't tell if those regions are cooler because they're more effective at dissipating the heat (I'd be surprised if it were that pronounced), or if there were a heat sink there if it would absorb and radiate some of that surrounding heat.

With your ducts, did you play around at all with sizing the ports that you're using to the sides?  I know you have one with and one without the sides, but just wondering if you played with larger vs smaller openings.  Also, did you play around with different lengths?  Mine is 5.6mm but only because that's the thickest material I had around - I could easily just use multiple ones to get more length, but wasn't sure if the gain between 5.6 and 25mm would be worth it (I read somewhere that you reached peak duct performance at 25mm for case fans, but who knows). 

I hope they'll work for you as well. You're looking at ~1h of sticking all 60 of them. They are quite small but they seem to be working quite well in my case. Anything else that I found to fit on the PCB had much shorter fins.

Your thermal camera is very useful. I wish I had one while playing with my miners. This temperature find is quite interesting. Since the area is in direct contact with the chip it doesn't make sense to be so cold and you can get a burn on touch. Can the material on the surface affect camera's thermal readout?

When I was developing the duct I played around with several parameters. I tried different lengths and went for the one that is short enough for a 40mm screw to hold along with the fan. I didn't go with smaller as this is really minimum. I couldn't make it smaller without affecting the airflow too much. I also tried different openings for the sides and realized that the most effective size is the one that just makes the air move instead of standing there, but nothing more. Outside heatsinks are completely ineffective compared to internal heatsinks, so you don't want to waste too much air on them.

I have my miners running for days, overclocked at 400MHz, in a room which reached temperatures of 45°C during the day this week, without overheating or a jump in HW errors. Hotter miner reached 79°C with hottest chips at 93°C actual temperature. So I can definitely say for myself that the duct properly serves the purpose I made it for. Default miner is not certified for ambient temperatures above 35°C at stock clock.

http://www.pohrani.com/f/22/13A/mloCMMC/s5-black.png

http://www.pohrani.com/f/34/13F/1EKOB0IU/s5-green.png

The reason I did it was more because my pull fan would hit the screws on the back of the case, so I wanted some spacing.  I believe what I've read is that around 1 inch (for case fans) is ideal length, anything more doesn't buy you anything - but I was surprised to see such a small space made such a big difference.

Why not cutting your own back of the case?

[innerchaos]

For those that dont have access to a laser cutter it can be done with regular tools.
 I am pretty handy with acrylic using a table saw with a plastic cutting blade and a router and also plastic cutting drill bits. ( I have built lots of fish tanks and sumps and various parts even dispaly cabinets and PC cases ). all of them look like you could have bought them in the store.. I certainly cant etch the bitcoin symbol but the rest of it is easy enough.

I thought about doing this.. but I am currently running mine in a vertical stand versus the horizontal placement.

do the Sides really add anything to the cooling process... that the original sides did not already provide.. yes I know the original sides were very thin plastic but if it just for air flow does it matter.

I am not sure if your laser cutter friend will crank these out for free or not.. but I have so much acrylic laying around. I can make a template and crank out 100 of these with just the scrap I have from previous jobs.

I use google sketchup for all my design projects what do you use ??