The good news is that it’s possible to cool AMD’s flagship Radeon HD 7970 GHz Edition to less than 75 degrees Celsius under full load, maintaining a quiet 32 dB(A) at the same time. The bad news? It'll cost you five expansion slots and more than $100.
One of our biggest complaints about AMD's Radeon HD 7970 GHz Edition is the card's noise under load. Its radial fan is loud enough to drive anyone who cares about acoustics insane. Particularly compared to the GeForce GTX 600-series cards that were already available, we're surprised that AMD didn't put more effort into improving its reference design. Fortunately, we've seen a number of board vendors implement their own aftermarket coolers to solve the reference board's noise problem.
It'd be laborious to do all of that work yourself. It'd cost a lot of money. And you'd void your warranty. But it seems like a better idea every day we have to hear our Radeon HD 7970 cards whirring away.
Rather than go the conventional route, with a two- or even three-slot cooler, we're taking Radeon HD 7970 cooling to an entirely different level.
Our installation requires three things to be successful: the right parts, five free expansion slots, and some patience and care. There’s no need to be afraid of dismantling your expensive new card, even if you've never done something like this before, so long as you follow our instructions. Just don’t expect a lot of help from the manual included with the heat sink we're using, the Alpenföhn Peter from cooling specialist EKL. You'll also find the Peter sold as Deepcool's Dracula here in the U.S.
By all accounts, this thing is a beast. And we're using it with modifications for AMD's Radeon HD 7970 GHz Edition in the form of new brackets and two Noiseblocker BlackSilentPro fans. All of this can be had for about $140 through a couple of different enthusiast-oriented online vendors. That's not cheap my any measure, but you get a lot of technology for the price.



Where do the additional two fans you haven't tested fit? I guess they might go in the empty slot, but that seems strange to me - why have a fan blowing directly into another fan.
its called push/pull you see it on cpu coolers and watercooling all the time. There are 120mm fans available
This looks just like an empty slot, but it is not enough and the mounting rail will not fit.
You can still mount up 2 fans horizontally or 140mm fans, but that brings no improvement.
There are 140mm fans available too, why are you telling me that?
http://extreme.pcgameshardware.de/luftkuehlung/182842-ekl-peter-lueftermontage-update.html#post3578374
http://www.hardwareluxx.de/community/f136/alpenfoehn-peter-821451.html
It looks like the bracket overlaps the heatsink, so the fans are much closer. Maybe it's just the angle.
Edit: They're on different cards, (a 570 and a 480, if my German isn't too bad), my mistake.
Edit:
I've experimented with different VRM coolers (on some photos you can see a slightly lower silver VRM heatsink) and slim fans but only the big black one (original from EKL) gives you the full performance.
The Gigabyte thing is in translation (I hope so)
The Windforce 5X @1,25 GHz is (under full load) quieter (!) than a Sapphire Toxic 6GB (1,2 GHz, Tahiti XT2) - thats fact. In a few minutes I will try a showdown between this two cards on 3840 x 3240 (6 cheap monitors, DVI only) and 3 active splitters.
Who wants to bet, can transfer me the money to my private account (which is unfair because I know the result - already)