Topic: Quieter fan for the S5 that puts out the CFMs? (Read 1173 times)

10c over stock doesn't sound so bad, how many ghash to lose to underclock it down if that isn't stable for long term?

Not sure what you define as long term, but I've had them running weeks at a time with the higher temps, without any sign of higher fail rates - running at the stock 350.  I'm not a fan of overclocking, so I never do it so can't comment on what the affects would be - but stock runs fine, zero change in error rates, etc.

Yes, a single one will keep it cool enough to run, but it will be about 10c above stock.  With two of them (push/pull) I ran about 5c over stock, or one in pull configure with my case ran about 5c over stock.

alh is spot on - just because the fan shown has a good CFM, doesn't mean that it's the right kind for cooling a miner.  In general, my best results were high static pressure (SP) on the intake, and high airflow (AF) on the exhaust... Even when they don't show the SP numbers, you can tell what kind of a fan it is by the blades.  To keep it simple, check out these two Corsairs - in particular, look at the ratio of blade to open space when looking straight on:

Look at the 5th photo - this is a high static pressure fan:
http://amzn.to/1PT7Fwn

Look at the 3rd photo - this is a high airflow fan:
http://amzn.to/1Az5R5d

Now the numbers as published by Corsair for these two, the SP fan does 62.74 CFM, and the AF fan does 63.47 CFM... But now let's look at static pressure, the SP fan does 3.1mmH2O and the AF fan does 1.1mmH2O, so the SP fan is almost 3x the static pressure.  

You may ask yourself why you'd ever even buy a AF can in this case, but it's other considerations - the AF moves the same CFM but at a slower RPM (so it's quieter), and at a lower power consumption (thus the lower RPM).

Another variable is the thickness of the fan, which effectively translates into the pitch that can be applied to the blades - so for SP fans, a 38mm will almost without exception outperform a 25mm.

So, the short of it is that for Antminers, what we're looking for is something with highest static pressure and moves a good amount air (don't even bother with something below 100CFM, it won't make a difference).  The one I linked in my first post is still the best bang for the buck hands down with >8 mmH2O (their stats show 80.66Pa, which is roughly 1/10 of mmH20.  All that for ~$12 which is less than half of most of these others.

The stock fan has furious CFM value, so the static pressure is not so important in this case I guess. 

You can always compare which 120x120 mm fan with 12V power is more preferable in the sense of noise, CFM and static pressure values at http://delta-fan.com/. 

Besides getting the airflow and fan dimensions correct, there is another less obvious item to consider for the S5 and I expect some other miners. What is the static pressure of the fan?  In other words how HARD does it push the air through the dense heatsink and such, not just the volume (i.e. the CFM measure) of air pushed. This I expect is to some extent what distinguishes the stock fan from most of the alternatives. It has a higher static pressure I am pretty sure. Static pressure is a less well advertised metric.

At least you should choose 120 mm section! But also keep in mind an airflow value, 120 CFM and higher is what you should seek for.

I mean if I were to search for S5 replacement fans on newegg.com, would I be looking at the 120mm fans section? http://www.newegg.com/Product/ProductList.aspx?Submit=ENE&IsNodeId=1&N=100007998%20600035590

The S5 stock is  120 x 120 x 38 mm  if that's what your asking ?

Is 120mm the right fan size for the S5?

http://www.amazon.com/gp/product/B00A460TK6?psc=1&redirect=true&ref_=oh_aui_detailpage_o00_s00     CFM is 190 and very quite i use a delta http://www.amazon.com/gp/product/B004Y1HLA8?psc=1&redirect=true&ref_=oh_aui_detailpage_o04_s00 as push one of these as pull .

I use Gembird DC120SF-12AS3 (120x120x38 mm, 3000 rpm, 124.74 CFM). I chose it because of price and availability.  Two of such fans cooling S5 perfectly for several months, and I can live in one house with S5. 

I've been on a quest to find a better fan also - I've tried literally everything off Amazon that was Prime, and a couple that weren't have finally been coming in.

I've tried the Noctua (both normal and 3000 RPM version), and while it's better than all the 2000 RPM ones, it still isn't close to the stock fan, even when doing a push/pull configuration.  I've also tried several Artic's, Corsair's, Cooler Masters, etc.  Unless you're running your S5 in Alaska, none of them are going to cut it.

The only one I've found that even comes close is this one:

http://amzn.to/1cn19f0

Plus it's actually one of the cheaper ones out there - sound wise I think it's better than the Noctua, and cooling wise it's DEFINITELY better.  With two of these in push/pull, I can get temperatures that are generally +5c over what the stock fan does - and they're definitely not what I would consider quiet fans, but the don't sound like the hurricane that the stock one does.

The only downside of these is that they're 3-pin instead of 4-pin, but you can just cut off the right tab (if you're got it with the tabs facing you), and it can be powered and report speed to the OS, but it won't be PWM speed controlled.

Anyway, hope that helps!

What do you all run for aftermarket fans on your Antminer S5s? Why did you choose this fan? Do you run the same fan front and back?

I went with the Scythe SY1225SL12SH for the exit fans and they're excellent. Very low noise (37 dba @ 1900 RPM) and they chuck decent air (110CFM). I wasn't able to find something with a higher CFM rating without sacrificing noise level, but I only did a few minutes search before buying. Unless someone can recommend another fan of similar or better specs (air flow to noise), I'll be replacing my front fans with those too.

Denis