Final fan mod to my s-5's

[philipma1957]

Legal bs:

A disclaimer :

 if you do this and fuck your gear up , your house up ,your life up, anyone elses life or gear  that is on you not me.

 This disclaimer   applies to anything I post on the site on mods or how

to setup  anything.

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link for 2 fans

http://www.ebay.com/itm/Delta-AFB1212SHE-Computer-Case-Power-Fan-120X120mm-Lot-of-2-/191472588964?pt=US_Computer_Case_Fans&hash=item2c94a7d8a4

Note a 3 day sale below:

 I used the evga 1300 g2  ATX-psu which comes with

1)a trick stating plug.
2) a molex 4 pin cable
3) a floppy disk adapter

the psu is on sale at new egg for  169
a rebate for 30 drops it to 139

http://www.newegg.com/Product/Product.aspx?Item=N82E16817438011&cm_re=evga_1300_g2-_-17-438-011-_-Product

http://images10.newegg.com/uploadfilesfornewegg/rebate/SH/EVGA17-438-011Jan15Jan1915lw82us.pdf

If you join ebates with this link you get 1% back down the road and I get a referreal

http://www.ebates.com/rf.do?referrerid=oRrlDoNKVpJcYkaEqnSWqg%3D%3D&eeid=26471


or join  on your own     >>>>>>  www.ebates.com     <<<<< 

    Put new egg in after you join and they send you to newegg's site  giving you 1% back

Even if you do not want to do ebates the new deal is very good for the evga psu. you can run 2 s-5's if you clock down to freq 325.

and the fan mod would make it quiet.




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okay here goes my final mod to my s-5 fans.

Mr Teal mentions that many psu's can supply 7 volts  on the 4 pin molex wires that come with the psu.

My Evga 1300 g2 can do this.

Your first step is plug in a 4 pin molex cable to you psu and check if it supplies 7 volts

bingo 7 volts



molex cable right into the evga 1300 psu



A 4 pin molex adapter cable  mine is to a floppy disk.   the wire you use needs 4 pins.

[philipma1957]

setup of adaptor cable

[philipma1957]

more space

plug in and test on the psu.

[philipma1957]

more space

connect to fans

[philipma1957]

space

[philipma1957]

space----------

So I get about 53db  I run the gear at freq 331  hash 1100

[philipma1957]

after some more time  I bumped to freq 343

pretty good just a little bit warm----------------  if you ran this in a cooler room you would get better temps. --------still db of fans are 53 and not a nasty pitch mod was under 20 bucks.

[philipma1957]

Okay I had a lot of people ask me about a fan controller for the s-5

I came up with a great cheap fan controller able to run 4 stock monster   loud fans.

this handles 100 watts. even more with a fan on it.

I feed this with a four pin molex cable directly from my evga psu.  that molex will feed 12 volts to this and the cable can handle 75-90 watts.  

item is only 12 bucks if you are willing to cut the wires on the stock fan it will run it quietly.

 http://www.amazon.com/gp/product/B00OT58TL4/ref=oh_aui_detailpage_o00_s00?ie=UTF8&psc=1

I dialed down the power to 9.5 volts and I am running 2 delta fans in push pull.

  gear is clocked to freq 381

[johnyj]

Are you sure if this kind of wiring would not disturb the output of the whole 12V rail since it is connected to a 5V rail? I think 5V rail and 12V rail have very different current

[philipma1957]

Are you sure if this kind of wiring would not disturb the output of the whole 12V rail since it is connected to a 5V rail? I think 5V rail and 12V rail have very different current

the molex four pin connectors on my evga can do 5, 7 or 12 volts.

If I use the 7 volt the two fans cool well  up to   freq 343.

If I use the 12 volt wires from the molex and use the amazon converter to drop power from 12v to  9.5v the 2 fans cool well up to freq 381.

These converters can take 12 volts from your psu  and drop the volts from 10 to 5 and anything in between.  Far better then a fan controller in that they will handle lot of fans.



http://www.amazon.com/gp/product/B00OT58TL4/ref=oh_aui_detailpage_o00_s00?ie=UTF8&psc=1


I will photo the hookup of it on sat.  I need some batteries for the camera.

[johnyj]

Are you sure if this kind of wiring would not disturb the output of the whole 12V rail since it is connected to a 5V rail? I think 5V rail and 12V rail have very different current

the molex four pin connectors on my evga can do 5, 7 or 12 volts.

If I use the 7 volt the two fans cool well  up to   freq 343.

If I use the 12 volt wires from the molex and use the amazon converter to drop power from 12v to  9.5v the 2 fans cool well up to freq 381.

These converters can take 12 volts from your psu  and drop the volts from 10 to 5 and anything in between.  Far better then a fan controller in that they will handle lot of fans.



http://www.amazon.com/gp/product/B00OT58TL4/ref=oh_aui_detailpage_o00_s00?ie=UTF8&psc=1


I will photo the hookup of it on sat.  I need some batteries for the camera.

Would it negatively affect the PSU since now it is under a strange load on different rails? Maybe for a fan it is ok, but will that introduce extra load for the rail of lower voltage?

Normally the current flows from 12V/5V/3V rail to the ground, but now the current flows from 12V back into 3V rail. If you connect some heavy load between 12V and 3V, and 12V is loaded by 20A, then 3V rail will have a negative current of 80A, is that safe? Usually PSU provide very little current for 3V rail, but that is for positive load

[sidehack]

The regulator he's linked is a switching regulator that takes in 12VDC and only 12VDC, then uses a high-current PWM pulse and lowpass LC filter to get an adjustable DC voltage lower than 12V out of it at relatively high efficiency. It does not put any load on 5V, 3.3V or anything else.

Additionally, if you connect a load between 12V and 3V then draw 20A, the 3V will see a -20A not -80A.

With a 4-wire fan, you can also get speed control by pulsing the PWM line (usually the blue wire). It takes an open-collector (or open-drain if using FETs) pulse driver, nominally around 24KHz, and the duty cycle determines the speed using the fan's internal circuitry. Something like that can be wired up with a 555 timer or some comparators in not very many minutes. There's no real load on the PWM line (milliamps), so you can control basically as big a fans as you want.

[philipma1957]

The regulator he's linked is a switching regulator that takes in 12VDC and only 12VDC, then uses a high-current PWM pulse and lowpass LC filter to get an adjustable DC voltage lower than 12V out of it at relatively high efficiency. It does not put any load on 5V, 3.3V or anything else.

Additionally, if you connect a load between 12V and 3V then draw 20A, the 3V will see a -20A not -80A.

With a 4-wire fan, you can also get speed control by pulsing the PWM line (usually the blue wire). It takes an open-collector (or open-drain if using FETs) pulse driver, nominally around 24KHz, and the duty cycle determines the speed using the fan's internal circuitry. Something like that can be wired up with a 555 timer or some comparators in not very many minutes. There's no real load on the PWM line (milliamps), so you can control basically as big a fans as you want.

this.

 I also  could have used  the cpu power cable and fed in 2x 12 volt wires  allowing for  more then 100 watts of power.

I am taking photos in a few minutes.

four pin molex with 12 volt power in this wire may be 16 ga not 18 ga but  18 ga can run 4 delta fans or 4 stock fans.  



that is the output end of the device . I will show the dc out on the next photo


dc out is  9.28 volts


here is dc in measure point


dc in is 12.16 volts



note room temp is 84 f and I have a low noise fan plugged into the  oem fan power I can keep the dc converter very cool this way


this is what I use  to test a lot of fans at one time.  the power device goes from 1 to 15 watts. and I use two grounding bars to  hook up 10 fans. the little part from amazon for 13 bucks can do the same as that power supply that cost 70 bucks.  and since the amazon dc converter feeds off the psu it is 95% of a 90%  psu or 85.5%
that 70 dollar power supply is 70-80 %  with 6 deltas or 6 oem s-5 fans you will save 10 watts

[judypug1956]

 any more testing?

[philipma1957]

Yeah I bumped the volts to 9.6 and the freq to 381

it runs just a little  too hot, but the room is 86f.

 1
30
381.25
67---------------Temp 67

2
30
381.25
61---------------Temp 61

Only    7 HW errors in 8 + hours

hash rate is 1261 at 655 watts.

I am going to open the window in that spare bedroom to drop temps a bit.

[johnyj]

The regulator he's linked is a switching regulator that takes in 12VDC and only 12VDC, then uses a high-current PWM pulse and lowpass LC filter to get an adjustable DC voltage lower than 12V out of it at relatively high efficiency. It does not put any load on 5V, 3.3V or anything else.

Additionally, if you connect a load between 12V and 3V then draw 20A, the 3V will see a -20A not -80A.

With a 4-wire fan, you can also get speed control by pulsing the PWM line (usually the blue wire). It takes an open-collector (or open-drain if using FETs) pulse driver, nominally around 24KHz, and the duty cycle determines the speed using the fan's internal circuitry. Something like that can be wired up with a 555 timer or some comparators in not very many minutes. There's no real load on the PWM line (milliamps), so you can control basically as big a fans as you want.

Thanks for pointing out my error. I had this question because I guess that you could just use 3V as ground and get 9V input for S5 to reach super high efficiency less than 0.3W/GH, is that possible with such high load on 3V rail?

Another way is to chain 3x12V output together to reach 36V, and then divided them into 4 chains of ASICs on S5, in this way you will also get 9V for the rig

Unfortunately I have no S5 at hand to test with

[sidehack]

Regulators typically aren't designed to sink current, but to source it. The 5V buck regulators on our PSU boards won't work as sinks so getting 7V across the 12-5 on them doesn't work. An actual high-current rail on a PSU is probably more readily able to work with sinking currents, especially if the current is quite a bit lower than what it's capable of handling in output. It kinda depends on the topology of the regulator. I wouldn't trust most things to handle reverse currents near high enough to power an S5, even at 9V loads.

I've thought about doing the 36V chain also, but I don't have any string miners to test with. Four boards on a Prisma would do it, except you'd need level shifters for the serial lines, which could be problematic. S5 there's no trouble stacking, since the only IO is ethernet, which is an isolated line independent of local ground references. You couldn't put two boards of an S5 in series on the same controller without smoking the controller, but four whole machines should work fine.

We're working on a prototype regulator for adjusting voltages for string miners; hopefully we have some good numbers in the next week or two.

[philipma1957]

Regulators typically aren't designed to sink current, but to source it. The 5V buck regulators on our PSU boards won't work as sinks so getting 7V across the 12-5 on them doesn't work. An actual high-current rail on a PSU is probably more readily able to work with sinking currents, especially if the current is quite a bit lower than what it's capable of handling in output. It kinda depends on the topology of the regulator. I wouldn't trust most things to handle reverse currents near high enough to power an S5, even at 9V loads.

I've thought about doing the 36V chain also, but I don't have any string miners to test with. Four boards on a Prisma would do it, except you'd need level shifters for the serial lines, which could be problematic. S5 there's no trouble stacking, since the only IO is ethernet, which is an isolated line independent of local ground references. You couldn't put two boards of an S5 in series on the same controller without smoking the controller, but four whole machines should work fine.

We're working on a prototype regulator for adjusting voltages for string miners; hopefully we have some good numbers in the next week or two.

looking forward to results on that.

BTW  this tiny little piece of gear I purchased on amazon is a very nice fan controller.

 If I choose to lower freq to 300 and volts to  8> I  would have a very quiet s-5  under 50 db running cool.
 I figure this small dc to dc converter can run 6 stock s-5 fans.

[cryptoglance]

Nice Mod! I will try this on my second S5.

As for now, I run 2x Silverstone SST-FHP141, both switched to performance mode running 1680rpm on each. Temps stay around 60c @ 343.75 frequency.

[alh]

Regulators typically aren't designed to sink current, but to source it. The 5V buck regulators on our PSU boards won't work as sinks so getting 7V across the 12-5 on them doesn't work. An actual high-current rail on a PSU is probably more readily able to work with sinking currents, especially if the current is quite a bit lower than what it's capable of handling in output. It kinda depends on the topology of the regulator. I wouldn't trust most things to handle reverse currents near high enough to power an S5, even at 9V loads.

I've thought about doing the 36V chain also, but I don't have any string miners to test with. Four boards on a Prisma would do it, except you'd need level shifters for the serial lines, which could be problematic. S5 there's no trouble stacking, since the only IO is ethernet, which is an isolated line independent of local ground references. You couldn't put two boards of an S5 in series on the same controller without smoking the controller, but four whole machines should work fine.

We're working on a prototype regulator for adjusting voltages for string miners; hopefully we have some good numbers in the next week or two.

looking forward to results on that.

BTW  this tiny little piece of gear I purchased on amazon is a very nice fan controller.

 If I choose to lower freq to 300 and volts to  8> I  would have a very quiet s-5  under 50 db running cool.
 I figure this small dc to dc converter can run 6 stock s-5 fans.

Just to be clear Phillip, are you only applying the voltage regulator to the single stock S5 fan? This essentially removes the S5's control of fan speed and turns it into a manual setting on the voltage regulator? Any other fan changes involved?

Thanks for your exploration of this area.