2x Asus HD 6970 Direct Cu II Overheating

RingleBell

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Sep 5, 2011
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My system:

Cpu: İntel Core-i7 2600k @4.6 Ghz
Memory: 2x Kingston Hyperx 4gb 1600mhz
Gpu: 2x Asus HD6970 Direct Cu II
Motherboard: Asus P8PZ68-V
Sound Card: Creative X-Fi Titanium
Chasis: Aerocool XPredator Evil Black
Operating System: Microsoft Windows 7 Ultimate 64 bit Service Pack 1
Screen: 1080p (1920x1080) @60hz over HDMI cable

Room temperature: 28C ~ 35C

Gpu Fan settings->
GPU FANS ARE AUTO when there is no 3d applications running.
GPU FANS ARE ALWAYS AT %100 SPEED when running 3d applicationg like games.

My problem is my bottom gpu is overheating. Because of my motherboard i have to use these two gpus very very close to each other.Each gpu uses 3 slots. I have a very very good air cooled chasis and i m using it's all fan slots. While ı bought a graphic card with good cooler why it's overheating ?(Just bottom card).

Gpu2 is the overheating card.
İdle temps are good. Gpu1: 37C Gpu2: 39C
But after a time in %100 load : Gpu1 : 68-69C Gpu2: Sometimes it stabilized in 90C, but sometimes it increases very very slowly to infinity.(These temps are taken while FurMark test)

Furmark Test Settings -> Resolation : 1920x1080
Anti-Aliasing: 8xMSAA
Dynamic Camera = On
Post Fx= On

Example furmark test(In this test overheating (bottom) card's temps are stabilized in 90C.But sometimes it goes to infinity very slowly.
2475.bmp


In games, temps are differs game to game. (All of the game's video settings set to ultra high).
Dragon Age 2 : I see Gpu2(max temp) 75C~
Stalker Shadow of Chernobyle : Max temp 80~
Stalker Clear sky: Maximum 90C
Crysis 2 + Directx Patch(tesellation) + Ultra high graphics patch :max 93 C

I see these maximum temps for a small amount of time only.
I think my bottom card is not reach very very high temps and it is not throttle itself because these games are not using two gpus
@%100 load all the time.My concern is in future some games can be use my gpus at %100 load for a longer time and my gpus will be reach very very high temps and even it goes up to restarting the pc.

In 3Dmark 2011 @ performance settings i see the bottom card's maximum temps 72C ~ 75C.

My chasis:
air-flow-o_1.jpg


I'm using all of the fan slots that my chasis provides , and fan directions are exactly like in the picture.

I tried to change gpu1's slot with gpu2's slot . (nothing changed)
I tried to insert an extra 120mm fan between the gpus for better air flow .(İts interesting that exactly nothing changed.i m expected at least a little change)
İf i use only one of the gpus (only gpu1 or only gpu2) temps are very good.



Should i concern about bottom card's temps?
What can i do for lowering the bottom card's maximum temps?
Is there anybody that can guarantee after six hours of gaming my bottom card wouldn't burn?



I'm tried to give you all of the informations about my problem.
If you have any idea about what can i do , please share it with me.

Please help me .
Thank you...

Note: All of my hardwares are new.So they can't be dirty.

Sorry, if my english bad : S



 
From what I've been reading it's very normal for the 6970's to get really hot.Although what's strange is that in a crossfire it's usually the top card that's most hot.As long as your not going over 90c then I don't see any problem.

If you want cooler temps then the next step would have to be water cooling.

Try leaving the case door off and see if the temps drop any.
 

stingstang

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May 11, 2009
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There are a few things you can do.
1. Make sure that your hard drives are not restricting the airflow from the front bottom fan of your case. Place them as high as you can, and remember, good wire management!
2. See if you can lift the case slightly. It looks as though there's a bottom vent in there that could get cold airflow through the bottom which would be sucked up to your 2nd GPU.
3. Make sure that the front fan (and bottom fan?) are flowing in, and the rest are flowing out.
4. See if the 2nd GPU fans are actually at 100%, and not just your top one. there may be a driver or software problem you overlooked.

Something you could have done.
Not buy 2 3 slot cards. It's really not necessary in a case like the one you have in normal applications to have a supercooled card. 3 slot cards aren't really made to be crossfired for this reason exactly.

One more thing. I highly doubt that you need both of those cards to play at 1080p resolutions. If you can't get your 2nd card's temp down, don't push it and end up killing that ~$240 card. Use one and sell the one you have. If you need to have 2 cards, buy a 2-slot version.