4 gh/s Ethereum farm - Running into expansion issues

[wtfcowisown]

Hello everybody!  I have 4 gh/s of gpu miners in a space I rented out nearby.  It looks like my 10000 cfm exhaust and intake vent are cooling it enough and my power situation is fine.  However, power density is now my issue.

I'm looking for a rig-building solution that does the following

- Allows me to build higher without heating problems.  Rigs are currently below 75 in 100-degree weather.  Most are in the 60's.
- Looking to exhaust the cards all in the same direction.

Currently, my cards are all exhausting away from eachother and into the next rack.  It works like this.

Intake vent > Card exhausting left > card exhausting right > space between rack > card exhausting left > card exhausting right > space between rack > exhaust fan.

The room is in the shape of a small storage container.  It's only 250 square feet so there's not much room to work with. My intent is to make it a wind tunnel.

Therefore,  my design needs to be like the following.

Intake vent > card exhausting right > space between rack > card exhausting right > space between rack > card exhausting right > exhaust fan.

This way the airflow will go in one direction in addition to the pressure drawn from the exhaust fan.

https://www.littlebigreddot.com/building-ethereum-mining-rig/

The first pic on this article is very much how my rigs look.  I put them each back to back so that they don't exhaust into eachother.  I put my rigs on metal racks that go 2 rigs high. 

Below is a picture of somebody going 3 rigs high.

https://www.indiamart.com/proddetail/36-gpu-gtx-1050ti-ethereum-mining-rig-576mh-s-18079252762.html

Anybody with bigger farms want to share their info?

[jstefanop]

Your going to run into issues with humidity when moving that much air in that small space. What happens when it rains, dew point reached at night, 100% humidity? Dew droplets at 10,000 CFM is like spraying down your rigs with a mist.

[wtfcowisown]

I'm not familiar with "dew points".  However, the intake vent is from a larger 100,000 sq ft warehouse that's dry.  That's where new air comes in.  I don't think I should be affected by any moisture then.  Am I wrong?

[curt999]

graphic cards dont exhaust in a particular direction other then up as the heat rises..you may want to space your exhaust fans evenly along the length of the racks..really no other choice to go higher unless you have more floor space..placing cards in a row one after another is not the optimum cooling solution since each card heats up the next..each card has a hot side (heatsink) and cool side (riser)..you may find going to three high and spacing the cards hot/cold/hot will work better..ie if hanging the cards on racks instead of parallel to each other hang them flipped 90 degrees

[Marvell2]

i have around the same amount of hash, i have six rooftop exhuast fans and its still not enough

Right now i found just opening the door and installing a screen door helps alot since th exhuast fans are sucking air though it.  We have heavy rains here and ive not had a humidity issue.

the gpus generate too much heat for humidity to form

[deskless]

I am stuck at 21 gpus only. Unable to run half of them due to unable to exhaust the hot air. I am just one apartment room for mining. Recently ordered window exhaust. Waiting to see if it would work.

[wtfcowisown]

graphic cards dont exhaust in a particular direction other then up as the heat rises..you may want to space your exhaust fans evenly along the length of the racks..really no other choice to go higher unless you have more floor space..placing cards in a row one after another is not the optimum cooling solution since each card heats up the next..each card has a hot side (heatsink) and cool side (riser)..you may find going to three high and spacing the cards hot/cold/hot will work better..ie if hanging the cards on racks instead of parallel to each other hang them flipped 90 degrees

This isn't true for my experience.  You can feel the exhaust coming out of the backs of my cards (opposite to the I/O).  I had my cards hanged vertically before, and it was terrible.  Changing the orientation saved me 30% on my temperatures.  When the cards were hanging the exhaust shot right back up into the card since heat rises.  I don't know if it's just my 6161kr 1060's, but that's how it is for me.  I agree with heating up the card to the next.  I suppose I'll just have to find racks that are the right size.

[crazydane]

I'm running about 2.8 GH/s (80 GPUs, all Nvidia, mostly 1080Ti's on the pill, but a good portion of 1070 and 1070Ti's as well).  I do have 3 1060 3GB rigs that are running HIVE,
 Total of 80 GPUs.

Here's a shot from 4:30pm today when outside temp was right at 98F and about as humid as it gets here in Central Virginia (which is very humid).  Temp inside the shop building was right at 100F.



I have a single 10,000 CFM intake fan, and a single 10,000 CFM exhaust fan.  I'm pretty pleased that temps stayed below 72C.  Some cards were running fans at close to 100% to maintain that, but only from about 2pm until 6pm.

[curt999]

yeah you can feel the heat coming off cards in a certain direction but what i meant is you cant control it like an antminer that can funnel the heat in one direction..if you went server cases when you could direct the heat in a predictable pattern then incorporate a hot cold side to your mining area with a barrier between the two..more upfront cost and possibly maintenence issues with fans etc however

[crazydane]

In my case I build a "room within a room" for force all incoming air through the rack holding all the miners.



Since the above pic was taken, both the left, right and ceiling have been dry-walled.  There is also a door behind that blue arrow to access the "inner room".  You can also see the 10,000 CFM exhaust fan in the top of the gable near the top of the pic.  Having an exhaust fan in addition to the intake fan is very important as you want to pull out the hot air generated by the miners.  I'm consuming right around 20 kW when the ASIC's are online as well.

View from the front:



Miners have been arranged a little differently since the above pic was taken and the open spaces have been sealed better to force the 10,000 CFM of air from the outside better.

Outside view of the intake without filters in place:



With 10 x 24x24 washable filters installed:



Even with very humid air, there is never any condensation issues since, no matter what, the GPUs are always hotter than ambient, even when it is 100F and humid outside.

[wtfcowisown]

I'm going to pm you with a few questions I have!

[evlo]

I have similar setup to crazydane - same rack shelves, only in blue color I don't have any active additional fans, then fans on cards, I run 100+ GPUS and I don't have any Issues. But I do have air outlets (without fans) on top of the racks with rigs. But I  have 10cm spaces between cards, rightmost cards are about 5C colder then left most cards, but I run fans at 50% speed tops. Ambient bottom 32C, ambient top 38C.

I must admit I would very much like to have my own car lift, but I still did not found country where to settle down :/

[pooparknoty]

Why would you not go the other way with the fans now that it is in cased in a room?  Suck the air through the miners and exhaust them to the outside?

[NiklasFalk]

Why would you not go the other way with the fans now that it is in cased in a room?  Suck the air through the miners and exhaust them to the outside?

Focused inlet with filters make an over-pressure in the whole building, and all the outlets can be whatever gaps etc.
Reverse things and you will have unfiltered (dusty) air seeping in everywhere, not very nice in the spring with all the pollen in the air.

[Marvell2]

use a swamp cooler to get u through summer