Post
Topic
Board Hardware
Re: [ANN] Spondoolies-Tech launches a new line of ASIC miners - Best W/GH/s ratio
by
timmah
on 20/05/2014, 20:39:32 UTC
There are blade design differences bearing differences motor differences etc. There are 40mm fans ranging from 10 dB to 100 dB. Again if someone wants to bother and look at what fan and what specs. they currently are, they can then source their own "better" or "quieter" equivalent.
A fan spinning at 6000~9000 rpm can never be quiet, no matter the bearing or blade design. It's impossible. At this level, you don't hear any noise from the ball bearing, you just hear the airflow. At this fan speeds, you will NEVER achieve laminar flow.

The bearing does matter if you look for fans spinning at 300~500 rpm. Then you even prefer a sleeve bearing over ball bearing, because sleeve bearing is more quiet. Again, at this level you only hear the mechanics of the fan, not the actual airflow. But for fans with many thousand rpm, ball bearing is the only option and turbulent airflow will always be noisy.

If you want a quiet SP10, go for watercooling.

I agree with the watercooling, a cold plate could be placed on the bottom but it will only draw heat from the one blade, although it could pull out enough heat to turn the fans down depending if a chiller is used and pump, etc.

The thing is that with more than a few of these the noise is an issue too, also the heat, with the concentration in such a small area I think that it is not able to pull all the heat out with the slimmer heat sinks and the smaller fans, even if it does pull 150cfm.  On a 42u Rack they have to be spaced about 4u apart or the heat from the miner below will affect the top.  These are sitting on rack trays and a lot of heat is actually dissipated from the bottom, it's hot enough to cook an egg Wink well with my contact thermometer it shows that the front of the heat sinks get to over 100c and is about the same on the bottom of the case.  The rack trays that I'm using has some vent holes and it helps a little bit but the entire tray gets hot as well so there is a large amount of heat transfer.  It's hot enough to burn my hand if I try to lift the miner from the bottom where the heat sinks are touching the case.  Over 100c as well.

From what I've looked at it may only cost a couple hundred at most for a single machine, cheaper of course with more since the same pumps and chiller would be able to be used for many miners.  Still for one miner it may be even less as I've seen some pumps that are less than $20 and would be able to move more than enough water though a cold plate...

I think I'm going to give this a shot and if it works I'll post some pics as I think that with one SP10 I may not even need a chiller as long as I have a large enough reservoir of water, I may hook it to a radiator that they sell on Amazon for about $40 and a 12" radiator fan which can also be found for about $20 on Amazon.

Oh, also to add where I live it gets very hot, up to 120f in the summer, my central AC does just fine but now with the extra heat from about 10Th of miners in total it can get toasty and this is sitting in a 10x15 sqft living room (which can not be used as a living room due to the sound) and my AC is on 100% of the time, there is air being exhausted out a window but it is not enough, on a good day and if the temp outside is below 85-90f I may get the living room ambient temp to about 85f but when it is hot like over 90f outside then it can get close to 100f inside.

This increases my power bill from not just the miners but also the AC on 100% at full blast all the time.  The bill is about $300-$400 more so it would likely be worth it to spend the one time costs to get water cooling system installed.  I'm not sure about others but it's worth the money as just one or 2 months would make up for the extra hardware, especially in the hottest part where it is over 120f in the day.

Just as a side note: if you use other cooling, you can use extra AC2DC power to get more out of the ASICs. The fans eat about 70 Watts - it's about 5% of the AC2DC power. If the cooling is effective and the ASICs stay cold, you also save on the leakage. So I would guess one could get more from such system.

Thanks for the tip, I can't wait to get the parts to try this out especially if it is efficient enough to take out some fans or lower them quite a bit more!  It's great that the new FW allows that to be done too!

Oh and on the cold plate price, it's a lot cheaper than it sounds, the cold plate does not need to be the exact size of the ASIC board just large enough to dissipate the heat that the miner generates, so some pricing for one that is a stock size which would work to dissipate all the heat from the bottom is about $100 as technically since it is pretty much the only place where the heatsinks touch the case and the board above it would still have to be air cooled unless the board can be flipped to touch the top of the case and I don't think that is a possibility.

So until someone makes custom sized cold plates for the boards to be swapped out with the heatsinks then we are stuck with cooling the bottom as much as possible...

Here is a list of some of my parts:

14" Fan for about $22 Shipped http://www.amazon.com/gp/product/B008FBTM6Y

or even bigger

16" Fan for about $33 Shipped http://www.amazon.com/gp/product/B002X1QV70

Radiator http://www.amazon.com/Hayden-Automotive-512-Performance-Transmission/dp/B000C3DDEA
OR
http://www.amazon.com/Hayden-Automotive-405-Ultra-Cool-Transmission/dp/B000C3F3HK
Both just under $40 especially if you have Amazon Prime. 

Thermal pad for the one radiator going under the unit $13 (Prime):
http://www.amazon.com/gp/product/B007PPEW52

Get a small pump on ebay, they have some that can move about 2.5 GPM for under $20 shipped.  If you choose a submersible one then they are even cheaper.

Some tubing and fittings etc should be $30 or less as each radiator comes with some tubing too but it looks a bit short.

There is not going to be a lot of pressure so PVC plumbing is not needed, tubing and some clamps should work just fine.

Chiller if you want $20-$200 or more but I'm going to try mine with out one and see how well it works, I figure with 2 radiators one on the miner one with the fan exhausting the hot water through the 2nd radiator out the window should work well enough, at least for one miner...

Total rough price with everything but a chiller $176, now if this can save $176 in extra AC cost for the summer it will already have paid for itself... Pump and Fan run on 12v easy to connect to a variety of PSUs and don't use more than 50-100w max.  So that is about the power of just 1 fan in the system!

Lets see what happens when it gets here and I put it together... Smiley  For me, it's worth the $176 or even $200 to turn the fans down to like 50% maybe less?  Also should help the AC cool even better since the heat does not have to be air circulated, a lot harder to control than water Wink