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I have an XFX Radeon HD 7970 Black Edition.

Newegg.com - XFX FX-797A-TNBC Radeon HD 7970 Black Edition 3GB 384-bit GDDR5 PCI Express 3.0 x16 HDCP Ready CrossFireX Support Video Card

Seeing as how it's still listed at $580 (maybe get updated when in stock), do you think it'll be able to Crossfire with this GPU?

Newegg.com - XFX Double D FX-797A-TDBC Radeon HD 7970 Black Edition 3GB 384-bit GDDR5 PCI Express 3.0 x16 HDCP Ready CrossFireX Support Video Card

Essentially, they're the same card excluding one has 2 fans and the other has 1 fan.

Oh, and more news. My mobo died after the warranty expired. After I ordered a new mobo and CPU. Bought these after I was disappointed with the AMD FX-8150's performance.

Newegg.com - Intel Core i5-2500K Sandy Bridge 3.3GHz (3.7GHz Turbo Boost) LGA 1155 95W Quad-Core Desktop Processor Intel HD Graphics 3000 BX80623I52500K
Newegg.com - Open Box: ASUS P8Z68-V PRO/GEN3 LGA 1155 Intel Z68 HDMI SATA 6Gb/s USB 3.0 ATX Intel Motherboard with UEFI BIOS\

Yes sure why not.

Quad-GPU SLI and Quad-GPU CrossFireX Support!

You mainboard has quad CF or SLI support and those GPU's are identical its just design that differs, so I dont see why not. You can do CF even with different GPUs its just that both will work with clocks of slower one. In your case they are the same so no problems.

Which PSU you have?

I'd suggest putting the dual fan model in the lower slot, the lower one is going to get hotter as it has less clearance to move hot air away from the card because the top card is blocking air flow.

You would also do well in removing one of the expansion card slot covers between the two cards, to try to increase air flow. Add another fan also to blow air either push or pull, right on the lower card.

YES, you can run CF on those cards.

[R-COM]MaSSive wrote:Which PSU you have?

Kingwin 1000w

Newegg.com - KINGWIN LZP-1000 1000W ATX 12V v2.2, EPS 12V v2.91, and SSI EPS 12V v2.92 SLI Ready CrossFire Ready 80 PLUS PLATINUM Certified Modular Active PFC Power Supply

I checked my power output with the PSU calculator and I'll only be drawing around 900w with the new CPU and dual GPUs and everything else. I'm also installing 2 more SSD drives for OS and ArmA 2 and DCS games.

Newegg.com - Kingston HyperX 3K SH103S3/120G 2.5" 120GB SATA III MLC Internal Solid State Drive (SSD) (Stand-Alone Drive)

[R-COM]LITOralis.nMd wrote:I'd suggest putting the dual fan model in the lower slot, the lower one is going to get hotter as it has less clearance to move hot air away from the card because the top card is blocking air flow.

Already had that in mind. I've read up a lot about crossfire before I made the decision to do it.

[R-COM]LITOralis.nMd wrote:You would also do well in removing one of the expansion card slot covers between the two cards, to try to increase air flow. Add another fan also to blow air either push or pull, right on the lower card.

Would you have any suggestions? I have the Cooler Master HAF932 case and it generates a lot of airflow through it as is.

If you got all or most of the fans in the HAF 932 running, don't worry about it for now.

[R-COM]LITOralis.nMd wrote:If you got all or most of the fans in the HAF 932 running, don't worry about it for now.

Yeah, the front, rear and side are all running on auto mode via my fan controller. They usually keep the case temperature around 27 degrees C. The top had to be removed for the radiator for my H100.

27 degrees C is good

are you planning on Overclocking the cards?

Usually with Crossfire and SLI, as long as the GPUs are the same model they are compatible. It is only recommended that they be the same model to eliminate any compatibility issues with varied PCBs. Considering that the only difference between these cards is a different cooling setup, they are 100% compatible.

[R-COM]rushn wrote:27 degrees C is good

I agree since they always run a 50% and at times 60% of their max RPM.

[R-COM]rushn wrote:are you planning on Overclocking the cards?

Yup. I had my single 7970 oc'd to 1125MHz. I think that's about as far as I can and want to take them on air cooling. In the future I'll look into a full liquid cooling setup, but I priced one out (CPU, 2 GPUs, both chipsets) and it was around $700. A little pricey for me now, but once I get done with school (18 months) I'll be rolling in the dough and throw some more upgrades in.

^Just felt like putting that in there.

Alright, so I've got the money together to do a crossfire, but have hit a little bit of a brick wall because of the new MOBO and the PCI slot layout.

Alright, so this is my MOBO:
Newegg.com - Open Box: ASUS P8Z68-V PRO/GEN3 LGA 1155 Intel Z68 HDMI SATA 6Gb/s USB 3.0 ATX Intel Motherboard with UEFI BIOS

The current layout of what I have plugged in is as such:
Top PCI-E x1-ASUS N15 wifi card
Top PCI-E 3.0-XFX GPU
Bottom PCI-E x1-N/A due to GPU
Top PCI-ASUS Xonar D1 sound card

The rest of the slots are open. My 2nd GPU will be plugged into the grey PCI-E 3.0 slot.

So here is the predicament I'm in. I want to use after market heatsinks on my graphics cards to lower the cooling. Right now my current one runs a 70c on stock heatsink, and I'm going to put the exact same one I have in. Now running 2 right next to each other will cause airflow and potentially heating issues. I've been looking at heatsinks and this is the one I have settled on if it is compatible to a 7970:
Newegg.com - ARCTIC COOLING Accelero XTREME Plus II Fluid Dynamic VGA Cooler for NVIDIA and AMD Radeon

Problem is that when it's installed, the GPU and it take 1 slot and cover 2 PCI slots, using 3 total. Problem? That means my sound card is not usable. Now, I've came up with a few options.

Option 1: Do nothing and use stock heatsinks. Not exactly in my plans.

Option 2 :Use the aftermarket heatsinks, kick the sound card to the curb and use the onboard audio. Not exactly what I want to do, but I would like to run my GPUs cooler. From what I read on reviews, most people temperatures dropped 20c after installing these heatsinks.

Option 3: Suffer with the stock heatsinks until I put enough money to do what I said in a previous post. Put together money and install a full liquid cooling system. Now, this is more along the lines of what I would like to do. Ever since building this rig I always have the urge to tinker with it and make it better and I think this option would bring it to it's full potential.

Basically, what's everyone's thoughts on this?

I say meh that heat sink. If it takes 3 slots, that is just bad. Maybe there is other solutions out there.

Liquid cooling = expensive. Heatsinks are the most expensive part of the kit. But if you can, go for it.

And I think last PCI Express slot is wired to 4x speed, but I might be wrong.

Cossack112 wrote:I say meh that heat sink. If it takes 3 slots, that is just bad. Maybe there is other solutions out there.

Liquid cooling = expensive. Heatsinks are the most expensive part of the kit. But if you can, go for it.

And I think last PCI Express slot is wired to 4x speed, but I might be wrong.

Yeah, the very last slot is a PCI-E 2.0 so I don't have anything I'll be using in it. I also feel the same way, those are big heatsinks for air cooling. I'm still giving it some thought.