GPU Cooling

[navydude]

Can someone help me figure the air flow needed to cool 11kw worth of GPUs. I have built a closet and am trying to figure what amount of air is needed to keep these cards at good temps mid 60s would be ok at this point. I will be using outside air to cool these cards. Right now temps are mid 90.

I know it may not the best setup but i dont have many options currently and losing money everyday these cards are not mining. I am using one of the 5 shelf wire racks with hanging cards 12 per rack along 2 mother boards and 2 power supplies. Pics will come soon.

I just need a good idea on how much air i need to pull through the closet to keep them running at decent temps. I was going to use a 1500 cfm 14" exhaust fan but im not sure that is enough. So before wasting money on materials i dont need please help me.

Thanks to anyone that can help. 

[Amph]

i don't know about the cost of those big fan that deliver 1500cfm, but with 3 noctua industrial(140mmx3 versus 4cm between each gpu plus 3.75cm for each gpu) you can cool down a rig perfectly, they can be pushed to 156 cfm and create a perfect tunnel between the gpu

assuming you have 16 rig, you need 48 of those and it's not cheap, around $1k

[navydude]

I have put a closet in a small storage room. Its jut a bit bigger than the rack on which these GPUs are mounted on. Its about 38" wide 24" deep and seven feet tall. I had some carpenter friends frame and sheetrock it. It will be air tight as to pull only the air from under the house ( not my cool air inside) as i put in another post. The 1500 cfm fan will pull about 3.4 amps as thats what the sticker says. Not worried much about that. Its going to be a confined space but with lots of airflow. Im just wondering if i should ad another fan to make 3000 cfm come thru this closet. I read some where that 12kw requires about 40,000 btu for cooling but i am not a hvac guy and not sure if this fan will pull enough air to remove the heat.

EDIT: I will have 9 Rigs each with 6 cards.

[duts_bg]

I have put a closet in a small storage room. Its jut a bit bigger than the rack on which these GPUs are mounted on. Its about 38" wide 24" deep and seven feet tall. I had some carpenter friends frame and sheetrock it. It will be air tight as to pull only the air from under the house ( not my cool air inside) as i put in another post. The 1500 cfm fan will pull about 3.4 amps as thats what the sticker says. Not worried much about that. Its going to be a confined space but with lots of airflow. Im just wondering if i should ad another fan to make 3000 cfm come thru this closet. I read some where that 12kw requires about 40,000 btu for cooling but i am not a hvac guy and not sure if this fan will pull enough air to remove the heat.

EDIT: I will have 9 Rigs each with 6 cards.

I think that more appropriate would be to remove  the warm air  with a suction fan and cold air must be pumped in with another fan. Otherwise it will not happen. The best solution for me is a room in which there is flow from opposite windows. In general, 90 degrees Celsius is slightly high, but not fatal. About 80 degrees already eligible. While find a solution to the cooling, you can  mining coin with less power consumption.

[navydude]

I will be pulling cooler air from under the house through the closet from the very bottom across  the cards and out the very top. The temp out side here is around 95-100F. I m not sure the temp under the house but it will cool the air slightly when pulling it from out side. (hopefully). I guess it will just be trial and error at this point to see if its going to keep enough air circulated to keep it cool. You would think that 90f air would be ok as long as the closet doesnt get any hotter than that and air is being constantly pulled out the cards would remain cool enough. Im just gonna continue the build. Will let everyone know what happens and post pictures when done.