Overclocking AMD's Radeon HD 7970 requires effective cooling, but the company's design is incompatible with most aftermarket heat sinks. Arctic and Deepcool claim to have solutions able to get the job done, without the reference cooler's loud fan.
The factory-installed GPU coolers used on today’s graphics cards are generally pretty specific. You can't yank the thermal solution from a GeForce GTX 680 and drop it onto a GeForce GTX 660 Ti. In contrast, the companies that design aftermarket coolers try to make them a lot more flexible, accounting for differences in mounting holes, PCB dimensions, and the varying power and memory circuitry found on one card to the next.
Occasionally, AMD or Nvidia modify things even more dramatically, introducing a new design that sends ripples of change through the aftermarket. And that's exactly what happened when the Radeon HD 7970 and 7950 emerged, both of which come with reference coolers that abandon the typically-flat cooling block design. Instead, they use a large, thick shim around the Tahiti GPU, putting it below the surrounding components and relying on a raised contact area for heat transfer away from the graphics processor.
Of course, this cooler design renders AMD's other implementations unusable on the Radeon HD 7900s. It also torpedoes the multitude of aftermarket designs intended to work with as many cards as possible. Most of the companies that manufacture graphics card coolers are used to dealing with dramatic changes, however, and as we wrote this story up, there were already two vendors selling new products to replace the problematic thermal solution covering AMD's Radeon HD 7970: Arctic's Accelero Xtreme 7970 and Deepcool's Dracula 7970. We previewed the Dracula (sold under EKL's name) in Extreme Air Cooling: Our Five-Slot (Quiet) Radeon HD 7970.

In addition, one other manufacturer came up with a way to use a more generic heat sink and fan combination on the Radeon HD 7900-series cards. The EK-VGA Supreme HF HD7970 Cu Adapter from EKWB Cooling Solutions is basically a copper shim that fills the space between a more standard cooling block and the Radeon HD 7970's Tahiti GPU.
Available at frozencpu.com for $4, the adapter is perhaps the least-expensive solution for anyone who already has an aftermarket cooler and wants to re-use it. But how much efficiency do you lose? After all, the adapter is responsible for transferring thermal energy between two surfaces that'd normally be touching, and paste on each.
In order to illustrate the effect of this, we're testing Arctic's Accelero Xtreme III with the copper shim installed and comparing it to the performance of Arctic's Accelero Xtreme 7970. The only functional differences between them are the shape of their cooling blocks and the presence of the shim.
Let's consider the other coolers we're testing, too:
| Reference Radeon HD 7970 Cooler | Arctic Accelero Xtreme 7970/III | Deepcool Dracula 7970 | |
|---|---|---|---|
| Dimensions: | 277(L) × 96(W) × 32(H) mm | 288(L) × 104(W) × 54(H) mm | 254(L) × 100(W) × 44(H) mm |
| Weight: | 764 grams | 653 grams | 556 grams (heat sink only) |
| Fans: | Single 75 mm radial fan | Three 92 mm axial fans | Up to three 120 mm or two 140 mm axial fans (none included) |
| Power Cables: | Four-pin graphics card fan header | Two graphics card fan headers (three- or four-pin) | Dual-fan to single-fan header adapter |
| Construction: | Copper Cooling Block and Cooling Fins | Copper Cooling Block, Five 6 mm Copper Heat Pipes, and Aluminum Cooling Fins | Copper Cooling Block, Silver Nickel Plating, Six 6 mm Copper Heat Pipes, and Aluminum Cooling Fins |
| Price | N/A | 7970: $80 (Newegg) III: $78(Newegg) | $75 (MSRP) not including Fans |
AMD's reference cooler for the Radeon HD 7970 doesn't need heat pipes; it instead uses a copper vapor chamber with an array of fins attached. A single 75 mm centrifugal fan pulls air in from the chassis and exhausts out the I/O bracket. Technically, this is the approach we prefer to see taken because it doesn't recirculate hot air inside your case, affecting other components. Unfortunately, the resulting temperatures are merely acceptable, and the noise generated in getting there is pretty unbearable under load.

Do you see the raised GPU contact surface on the vapor chamber? This is what makes the Radeon HD 7900-series cooler unique.


Below is a picture of the naked reference card, showing the thick protective shim surrounding AMD's Tahiti GPU.
This surely looks impressive (giant graphics card and oversize heat cooler), but is this "eye candy" for the technically inclined PC enthusiast really moving forward, or just another pile of copper pipes sold at a price established out of pure value perception? This article got me thinking... Are we unknowingly creating a market demand for cooling products that make little sense in the grand scheme of things, nor shows little technological advancement? Why do we get so excited when a graphics card becomes so hot during peak operation that it requires cooling beyond standard specification. In engineering terms, any system that transforms such a large amount of electrical energy into heat as a side effect would be considered inefficient. By creating a market for "aftermarket" cooling, we do not only show our tolerance for inefficiency, but also create a booming demand for lackluster "solutions".
But, would be nice to see the coolers compared to some mainstream solutions. IE the HIS IceQ X2 or Sapphire Toxic, etc. etc.
But, would be nice to see the coolers compared to some mainstream solutions. IE the HIS IceQ X2 or Sapphire Toxic, etc. etc.
btw nice article
This surely looks impressive (giant graphics card and oversize heat cooler), but is this "eye candy" for the technically inclined PC enthusiast really moving forward, or just another pile of copper pipes sold at a price established out of pure value perception? This article got me thinking... Are we unknowingly creating a market demand for cooling products that make little sense in the grand scheme of things, nor shows little technological advancement? Why do we get so excited when a graphics card becomes so hot during peak operation that it requires cooling beyond standard specification. In engineering terms, any system that transforms such a large amount of electrical energy into heat as a side effect would be considered inefficient. By creating a market for "aftermarket" cooling, we do not only show our tolerance for inefficiency, but also create a booming demand for lackluster "solutions".
this applys to all mid-high end nvidia/ati(amd) video cards
That's how you transfer heat from the shim to the unmodified Accelero III. I wonder if JB Weld would work better...although that would permanently attach the shim to the Accelero III.
@cilliers
The value is in the noise reduction at load. These processors run hot because they are doing a great deal of work pushing electrons around. Consider that incandescent bulbs work the same way - the friction causes the filament to get so hot that it glows. If you don't want a thermally hot/power hungry card for philosophical reasons, then don't buy one.
@W(h)yKnott
I imagine that "Dracula" is intended to connote sucking the heat away from the 79xx. The fact that these tests show that they are relatively inefficient at doing so makes for a humorous double entendre, like your handle.
Unless you don't like not burning the GPU, pretty much. You might get away without it, but temps would be far higher. Maybe if you really lapped the cooler and shim you could get away with it, but I'd doubt that using no thermal paste at all would be a good idea even in that situation.
Absolutely. If you don't, contact wouldn't be uniform and you'd have dead spots.
Thermal paste is important, but the trick is to use as little as necessary, not to slather on gobs.
Its very unlikely that someone with such card is going to have air cooling "upgrade", since the WC setups are afordable. If that person wants to get better cooling solution, he wouldnt spend money on air cooling, just throwing on it an radiator or connect the GPU block to an existing radiator would be sufficient, better for looks, and better performance.
If I had a card that used 1000 watts of power but was ten times faster than the Radeon 7970 in every way, it would still be the most energy efficient graphics card in the world today. I also don't think that after-market VGA cooling is a booming market for lackluster solutions. The after market VGA cooling industry probably isn't booming because even the minority of overclockers in this world tend to not use an aftermarket cooler on their graphics card(s). Even then, just because there are some lackluster solutions doesn't mean that they sell nearly as well as the good solutions.
I buy aftermarket coolers for noise reduction only, I can't stand a loud computer. Now my machine is so quiet, it's hard to tell whether it's off or on, even when it's under load.
And having more efficient hardware wouldn't help with the noise, the OEMs would just put smaller coolers and smaller/faster fans, so noise output would be similar.
Review the dracula with two 140mm fans or three 120mm fans as the design was intended, to show optimal performance.
Overclock as far as you can with each design so we can see the value added to the card.
Without that information this entire article is pointless, and leads to dumba$$ comments like 'why dracula, because it sucks?'
How about review the design as it was meant to be used?
*And what kind of a tech journalist doesn't have a few spare 120/140mm fans laying around? WTF!!!
The 7970 doesn't NEED more, temps were awesome. Noise, space, and cost also comes into play.
You think a slight temperature difference between the Dracula and Accelero will affect the overclock? That's just silly. Limits will be set by voltage unless temps are astronomical.
Overdramatic complaint is overdramatic.
OC most silicon chips, and they will lose efficiency.