How much heat a rig dissipate ? | Bitcointalksearch.org

Trillium

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Quote from: razorfishsl on July 19, 2013, 06:13:25 PM

Quote from: HellDiverUK on July 16, 2013, 07:32:28 AM

Quote from: fran2k on July 12, 2013, 01:43:22 PM

The rigs will have 3 Sapphire 7950, any of latests intel cores and one 700w 80+ PSU.

Good luck running 3x7950 off a 700W PSU. I run 2x7950 and it's using ~700W at the wall, that's using a 1000W Zalman PSU. CPU is a i3-3225, SSD drive, 2x4GB RAM, nothing else.

See: https://bitcointalksearch.org/topic/power-supply-watts-for-3-7950-240670

Don't just look at it that way.....
Find the PSU sweet spot... all switched mode PSU have an efficiency curve that looks like an umbrella(yep even the bullshit 80's)
You need to be at the 'top' of the umbrella.. doing so can save you 10-15% of your power requirements...

This. But sadly many manufacturers (especially the cheaper ones) will not provide this information. And it would be tedious to produce the data for the curve yourself. To get a DC variable load, a dedicated geek might want to buy some cheap 100+ watt variable wirewound ceramic cored resistors from one of the cheap Chinese vendors (dhgate, ebay, uxcell etc) although it might still be annoying trying to simulate a realistic DC load spread out across the different rails.

example: http://www.uxcell.com/100w-500-ohm-ceramic-tube-wire-wound-variable-resistor-p-143091.html

Or you could just make your own such resistor with some even cheaper furnace element wire and a brick Tongue

razorfishsl

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Quote from: HellDiverUK on July 16, 2013, 07:32:28 AM

Quote from: fran2k on July 12, 2013, 01:43:22 PM

The rigs will have 3 Sapphire 7950, any of latests intel cores and one 700w 80+ PSU.

Good luck running 3x7950 off a 700W PSU. I run 2x7950 and it's using ~700W at the wall, that's using a 1000W Zalman PSU. CPU is a i3-3225, SSD drive, 2x4GB RAM, nothing else.

See: https://bitcointalksearch.org/topic/power-supply-watts-for-3-7950-240670

Don't just look at it that way.....
Find the PSU sweet spot... all switched mode PSU have an efficiency curve that looks like an umbrella(yep even the bullshit 80's)
You need to be at the 'top' of the umbrella.. doing so can save you 10-15% of your power requirements...

MikeCryptoIndustries

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I ran 20 x 5870 gpus in 5 quad rigs for a few years. I often saw room temps of 28-30c when cards ran at 85c

HellDiverUK

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Quote from: fran2k on July 12, 2013, 01:43:22 PM

The rigs will have 3 Sapphire 7950, any of latests intel cores and one 700w 80+ PSU.

Good luck running 3x7950 off a 700W PSU. I run 2x7950 and it's using ~700W at the wall, that's using a 1000W Zalman PSU. CPU is a i3-3225, SSD drive, 2x4GB RAM, nothing else.

See: https://bitcointalksearch.org/topic/power-supply-watts-for-3-7950-240670

Trillium

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Refrigerative air conditioning will greatly increase your costs. You say the "The median temp. of the zone is 0-35 C." well that is warm but not outrageously hot... you could setup some fans and ducting to move the heat outside. If you exhaust the hot air from the GPUs well enough the room temp wont rise assuming the cool air inflow is sourced some ways from the exhaust location. You won't be the first miner to operate rigs in 35 C weather without AC.

http://www.amazon.com/s/ref=nb_sb_noss?url=search-alias%3Daps&field-keywords=duct+fan

razorfishsl

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Really there should be no need for aircon.
Design your environment correctly, pull out hot air from top of roof space, bring cold air in bottom and try to limit the volume, glass/ metal box made double/triple height size of equipment.

Anything else is just pissing into the wind.... making the utility company rich.......

3ham3

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These work well but really it depends on your total rigs, great for a basement with no windows to vent hot air out..

http://www.movincool.com/portable-air-conditioners/classic-plus-14

fran2k

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Quote from: Photon939 on July 12, 2013, 05:28:16 PM

Computers dissipate nearly 100% of all input power as heat. One watt of electrical power converts to 3.41 BTU/hr of heat. So all you have to do is multiply your electrical consumption of all the devices in watts by 3.41 and then you will have the BTU requirement for your AC system. Buffer that a bit to account for sun and heat infiltration through the walls and you should have a pretty good idea of what you will need.

Ok, thanks for your answer!

Photon939

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Quote from: fran2k on July 12, 2013, 01:43:22 PM

I'm planning the setup for a lot of GPU mining rigs and I need to figure out how to cool the place.

Can you give and estimate?

The rigs will have 3 Sapphire 7950, any of latests intel cores and one 700w 80+ PSU.

The median temp. of the zone is 0-35 C.

Can you help me figure out how to cool the place if necessary for about 20 rigs in one medium/big room?

How much energy this will dissipate?

Computers dissipate nearly 100% of all input power as heat. One watt of electrical power converts to 3.41 BTU/hr of heat. So all you have to do is multiply your electrical consumption of all the devices in watts by 3.41 and then you will have the BTU requirement for your AC system. Buffer that a bit to account for sun and heat infiltration through the walls and you should have a pretty good idea of what you will need.

dogjunior

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12000 BTU / 1 ton will cool 400 square feet of space. So if you have 2000 square feet then a 5 ton cooling unit will be the minimum. I would double the cooling for that many rigs.

fran2k

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I'm planning the setup for a lot of GPU mining rigs and I need to figure out how to cool the place.

Can you give and estimate?

The rigs will have 3 Sapphire 7950, any of latests intel cores and one 700w 80+ PSU.

The median temp. of the zone is 0-35 C.

Can you help me figure out how to cool the place if necessary for about 20 rigs in one medium/big room?

How much energy this will dissipate?

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