Dual GPU Cooling Advise

NexCyber

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Feb 9, 2009
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Ok. For you hardcore OCers. I got the CoolerMaster V8 for my i7 after reading many reviews. Now, I have the Asus Rampage II Extreme and a Radeon 4870x2 due here in a day. I plan on OC this rig to 3.8, and from what I have read, these GPUs are hot. THese are dual slot GPUs, and if you look the layout of Rampage II Mobo, it appears two of the 4870x2s in the blue PCIe 16 slots would seem to be very close, thus hot hot hot.
http://eprim.org/i/0809/asus-rampage-ii-extreme.jpg

Now, the GPUs blow air out the back of the card itself to the outside of the box, and, I am considering mounting and additional fan on the side of the case (CM Sniper) to provide more air. Im still a bit concerned, as several reviews over at Newegg stress how hot these cards get under load. I saw one guy who has water blocks, but he has ample space in between and I never messed with water. So, what are my other options as I will surely add a second GPU when the prices fall some more. Gotta use the blue slots for dual 16 crossfire. Almost seems like one GPU wont be getting a lot of air or am I overlooking something. Your help is appreciated big time.
 

xthekidx

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Dec 24, 2008
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I would say water cooling is your best option for 2 of those cards on that mobo. I have the P6T which has a very similar layout when looking at the PCIEx16 slots and I can attest to the fact that there is almost no space between them if another card is added, I have the GTX 260 right now which is a similar size. You can buy a small water cooler for just one video card, which I would put on your card in the first x16 slot, then use your other air cooled card in the second slot so it gets the air to its fan. If you used two air-cooled cards, then the fan of the first card would be right up against the next card, and get almost no airflow, the only air it would get would be hot off the back of the second card. If you wanted to use just air cooling for two of those cards, I would say you need a different board, such as the P6T deluxe which has better spacing between the first two PCIEx16 slots. I think two air cooled cards on that mobo will get too hot unfortunately :(

Here is an image of the deluxe with the better spacing:
http://images.bit-tech.net/content_images/2008/08/asus-p6t-deluxe-next-generation-x58-motherb/P6T-Deluxe_supper.jpg
 

NexCyber

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Well, I have two dell 24" 1920x1200 LCDs and a 26" Sony Bravia 1080p I was hoping to utilize (blu ray combo) eventually. Since I will have the blu ray and HD comcast, and the two dells have independant PIP, I think I can do some pretty neat things and utilize the extra power. I wont buy a second card immediately as I said, but I would like to know ahead of time should a heat issue arise. I did find a bios/fan/voltage thread on another forum.
 

theAnimal

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One HD4870x2 is plenty for 19x12. You can only game on one screen. You don't need a high powered card to play movies. Just add an HD4350 for the third monitor.

Since the card exhausts out the back, heat should not be a big problem.
 

xthekidx

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But with the cards so close together, I don't think any air would get to the first card :/ so heat would not really be exhausted out the back of the first card because air would not be really moving through it. I might be wrong here though, but it doesn't seem like the first card would get enough airflow to me.
 

theAnimal

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I suggested only using one 4870x2, since 2 don't scale well and are also unnecessary for that resolution.

I would think that a good side intake fan would take care of any airflow problems.