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Other => CPU/GPU Bitcoin mining hardware => Topic started by: Kinetic915 on April 26, 2013, 03:18:33 AM



Title: Best fan setup/best fan?
Post by: Kinetic915 on April 26, 2013, 03:18:33 AM

Hey all,

Do you find the best possible cooling solution is shooting the air directly horizontally at the card, shooing inbetween cards, from the side the ports are on, or shooting air in on a upward slope.  I currently have 2 fans cooling 3 7950s and find the temps varying from 66 on the first outer card to 75 on the last.  Do most 7000s/6000s pull air in from the side and shoot upwards/out the top of the card?

Thanks!
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Title: Re: Best fan setup/best fan?
Post by: induktor on April 26, 2013, 03:32:46 AM
Hello
I have tried several configurations but every one lower one of the cards temp and turn up on other cards, so It's not very clear.
I think that open case design is the best solution ATM, I'm running 4 x 7850 in a custom-made aluminium frame, and the highest temp I have is 61 C with 27 C ambient

I even bought the antec big-boy (200mm big ass cooler) but no improvements, it seems that this solutions interferes with the card coolers.

something that DID work, was put a electronics fast motherfucker 120mm cooler over the PSU, since most psu aims to work SILENTLY and "at very high temps" which will reduce lifetime, so I put over the original cooler (outside of the psu) a fast 2000 rpm 120mm cooler,to keep it at a reasonable 30 degrees C instead of nearly 50 with original cooler! sick!


Title: Re: Best fan setup/best fan?
Post by: Kinetic915 on April 26, 2013, 03:37:44 AM
Hello
I have tried several configurations but every one lower one of the cards temp and turn up on other cards, so It's not very clear.
I think that open case design is the best solution ATM, I'm running 4 x 7850 in a custom-made aluminium frame, and the highest temp I have is 61 C with 27 C ambient

I even bought the antec big-boy (200mm big ass cooler) but no improvements, it seems that this solutions interferes with the card coolers.

something that DID work, was put a electronics fast motherfucker 120mm cooler over the PSU, since most psu aims to work SILENTLY and "at very high temps" which will reduce lifetime, so I put over the original cooler (outside of the psu) a fast 2000 rpm 120mm cooler,to keep it at a reasonable 30 degrees C instead of nearly 50 with original cooler! sick!

haha nice, wow 61C at 27C ambient its usuall 24-27C ambient for me with 75C high. Damn. I tried building a fan on top venting into a tube to pull the air off, but that didnt work and raised the temps somehow.....


Title: Re: Best fan setup/best fan?
Post by: crazyates on April 26, 2013, 04:40:29 AM
I assume these are open air rigs? Or are they in a case?

I think it really depends on the cooler for your GPU. Stock blower coolers are really nice cuz they vent almost all of the hot air outside of the case. Ideal for a GPU inside a case. OTOH, my 7970 is a tri-fan WF3, and blows air up and down, rather than outside. It just circulates the hot air back into my case. I actually get better temps if I leave the side of my PC case off. If these were in an open-air rig on risers, you wouldn't even need any other case fans.

This is a stock cooler, along with a radial, like what's used in the 6990:
http://hothardware.com/articleimages/Item1796/small_Radeon-HD-7950-6.jpghttp://cdn.overclock.net/9/96/525x525px-LL-963a1292_vbattach216587.pnghttp://images.bit-tech.net/content_images/2012/08/amd-radeon-hd-7950-3gb-with-boost/7950-4-1280x1024.jpg

This is what mine looks like:
http://www.legionhardware.com/images/review/Gigabyte_Radeon_HD_7870_OC/Image_01S.jpghttp://www.gigabyte.rs/microsites/data/92/page-06.jpghttp://images.tweaktown.com/pr/7/5/7518_02_gigabyte_unveils_geforce_gtx_660_650_overclock_edition_graphics_cards.jpg


Title: Re: Best fan setup/best fan?
Post by: Kinetic915 on April 26, 2013, 06:09:03 AM
gotcha, did you just get those graphics from google?


Title: Re: Best fan setup/best fan?
Post by: induktor on April 26, 2013, 01:54:14 PM
I assume these are open air rigs? Or are they in a case?

Nice Graphics!!!
My cards are dual cooler Sapphire series, and they blow air top, bottom, front and back.
while most of the heat is blown top, there is also significant air going bottom and front.

Yes open custom made aluminium frame, 4 cards per rig.

I used to have two cards in one standard pc enclosure but it was impossible to cool, no matter what I do, one of the cards go above 75 degrees C (with 70% speed fan), so I have to shut it down.
I even tried installing 5 fast coolers (4000 RPM) 1 front, 2 at side over the cards, and 2 back taking the hot air out, but no go, the less worst solution was leave the case open, but still one of the cards remain at 68 degrees C or so.

same rig, in open, custom made, aluminium frame, is between 48 and 61 degrees C with fan at 60% speed and 27 C ambient temperature, so it is very clear that open desing is the way to go here :)



Title: Re: Best fan setup/best fan?
Post by: dogie on April 26, 2013, 02:38:06 PM
In an open frame, try and work with natural convection currents you'll be creating in the room. That is, the hot up draft you are creating.

If you can get a fan below parallel with the motherboard, that will really help carry the hot air away from the cards and reduce air pressure surrounding them [simplified]. = easier for the card to exhaust more air.


Title: Re: Best fan setup/best fan?
Post by: crazyates on April 26, 2013, 03:34:46 PM
gotcha, did you just get those graphics from google?
Ya I just google image searched a few pictures, just to illustrate. I find it's easier to help comprehend where your hot air is going.

I used to have two cards in one standard pc enclosure but it was impossible to cool, no matter what I do, one of the cards go above 75 degrees C (with 70% speed fan), so I have to shut it down.
I even tried installing 5 fast coolers (4000 RPM) 1 front, 2 at side over the cards, and 2 back taking the hot air out, but no go, the less worst solution was leave the case open, but still one of the cards remain at 68 degrees C or so.
68-75C is actually acceptable for a GPU, but you might try upping the GPU fan itself. Try increasing it from 70% to 90% and see what you get for temps.

In an open frame, try and work with natural convection currents you'll be creating in the room. That is, the hot up draft you are creating.

If you can get a fan below parallel with the motherboard, that will really help carry the hot air away from the cards and reduce air pressure surrounding them [simplified]. = easier for the card to exhaust more air.
The best example I've seen of that was Catfish, and his vertically mounted GPUs, seen HERE (https://bitcointalk.org/index.php?topic=68776.msg809995#msg809995). Imagine of those were stock blower GPUs, blowing the hot air up and away from everything. You would never worry about hot air circulation ever again! :P


Title: Re: Best fan setup/best fan?
Post by: Kinetic915 on April 26, 2013, 05:15:42 PM
@dogie do you mean a fan blowing air horizontally at the level of the motherboard?