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AMD Radeon HD 7990: Eight Games And A Beastly Card For $1,000

AMD Radeon HD 7990: Eight Games And A Beastly Card For $1,000
By , Igor Wallossek

We've been waiting for this since 2011. AMD is ready to unveil its Radeon HD 7990, featuring a pair of Tahiti graphics processors. Can the dual-slot board capture our hearts with great compute and 3D performance, or does Nvidia walk away with this round?

Time flies. We published AMD Radeon HD 7970: Promising Performance, Paper-Launched almost a year and a half ago. The graphics card market was quite a bit different back then. AMD’s virginal Graphics Core Next architecture made its debut against Nvidia’s Fermi-based GeForce GTX 580, absolutely blowing the company’s own Radeon HD 6970 out of the water in the process.

And a dual-GPU card, based on two of the 7970’s Tahiti GPUs was rumored to be right around the corner. We waited. And we waited.

Of course, in the 12 months that followed, no official Radeon HD 7990 surfaced. Rather, board partners tentatively dipped their toes into that high-end space. PowerColor got out ahead of the rest with a dual-Tahiti offering that consumed three expansion slots, required three eight-pin auxiliary power connectors, and screamed like a banshee any time we applied a load to it. HIS followed suit, giving us exclusive access to a couple of prototypes before withdrawing its plans to ship a dual-GPU solution altogether. Finally, Asus threw its hat into the ring with a liquid-cooled card of its own, as obscenely-priced and limited as it was. We looked at all of them in Asus' ROG Ares II: Four Dual-GPU Graphics Cards, Compared, eventually coming to the conclusion that Nvidia’s GeForce GTX 690, while a bit slower in our benchmarks, made more sense than any of the Radeons.

Challenge accepted, AMD said. Today we have a real, actual Radeon HD 7990, straight from the company’s own product team. It’s a dual-slot card. It only requires two eight-pin power connectors. And—brace yourself—its fans spin quietly. That’s not to say the 7990 is silent, but more on that later.

Hold Nothing Back In The Name Of Performance

Stripped down to its bare PCB, the Radeon HD 7990 consists of two Tahiti GPUs, each surrounded by 3 GB of GDDR5 memory and connected by a PLX Technology PEX 8747 switch.

The graphics processors are complete—AMD doesn’t disable any of their resources, so each brings 2,048 Stream processors to the table, along with 128 texture units, 32 ROPs, and an aggregate 384-bit memory bus. The company even sets the GPUs to operate at 950 MHz, with a 1 GHz boost state. That’s a little faster than the vanilla Radeon HD 7970, and a bit slower than the later GHz Edition version, which starts at 1 GHz and accelerates to 1.05 GHz.

The 3 GB of GDDR5 memory attached to each GPU runs at 1.5 GHz, just like AMD’s Radeon HD 7970 GHz Edition (in comparison, the original 7970 launched with a 1,375 MHz memory clock), delivering up to 288 GB/s per GPU.

Nestled between the two 4.3 billion-transistor chips is that PEX 8747 switch—the same one Nvidia uses to enable inter-GPU communication on the GeForce GTX 690. The 48-lane, five-port device is manufactured at 40 nm and is PCI Express 3.0-capable. So, it attaches to each GPU through a 16-lane link, and then to the host interface with an additional 16 lanes.

All of that hardware is used to enable up to five simultaneous display outputs, one of which comes from dual-link DVI and four of which get exposed through mini-DisplayPort connectors. In comparison, Nvidia’s GeForce GTX 690 can only do four monitors in a three-plus-one configuration. Five screens in a 5 x 1 arrangement make far more sense to productivity-oriented enthusiasts.

At least based on its raw specifications, the Radeon HD 7990 is technically closer to two 7970 GHz Editions in CrossFire than GeForce GTX 690 is to two 680s in SLI. And given the massive performance boosts we’ve seen from AMD’s driver team over the last year, the paper promise is a compelling advantage that should make this the fastest dual-slot graphics card in existence. Now, what about the rest of the board’s vitals?


Radeon HD 7990
Radeon HD 7970 GHz Ed.GeForce GTX Titan
GeForce GTX 690
GeForce GTX 680
Shaders2 x 2,048
2,0482,688
2 x 1,536
1,536
Texture Units
2 x 128
128224
2 x 128
128
Full Color ROPs
2 x 32
3248
2 x 32
32
Graphics Clock
950 MHz
1,000 MHz836 MHz
915 MHz
1,006 MHz
Texture Fillrate
2 x 121.6 GT/s
128 Gtex/s187.5 Gtex/s
2 x 117.1 Gtex/s
128.8 Gtex/s
Memory Clock
1,500 MHz
1,500 MHz1,502 MHz
1,502 MHz
1,502 MHz
Memory Bus
2 x 384-bit
384-bit384-bit
2 x 256-bit
256-bit
Memory Bandwidth2 x 288 GB/s
288 GB/s288.4 GB/s
2 x 192.3 GB/s
192.3 GB/s
Graphics RAM
2 x 3 GB GDDR5
3 GB GDDR56 GB GDDR5
2 x 2 GB GDDR5
2 GB GDDR5
Die Size
2 x 365 mm2365 mm2551 mm22 x 294 mm2294 mm2
Transistors (Billion)
2 x 4.31
4.317.1
2 x 3.54
3.54
Process Technology
28 nm28 nm28 nm
28 nm
28 nm
Power Connectors
2 x 8-pin
1 x 8-pin, 1 x 6-pin1 x 8-pin, 1 x 6-pin2 x 8-pin
2 x 6-pin
Maximum Power
375 W
250 W250 W
300 W
195 W
Price (Street)
$1,000
$430$1,000
$1,000
$460
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Top Comments
  • 26 Hide
    cangelini , April 23, 2013 9:53 PM
    donquad2001this test was 99% useless to the average gamer,Test the card at 1900x1080 like most of us use to get a real ideal of what its like,only your unigine benchmarks helped the average gamer,who cares what any card can do at a resolution we cant use anyway?

    If you're looking to game at 1920x1080, I can save you a ton of money by recommending something less than half as expensive. This card is for folks playing at 2560 *at least.* Next time, I'm looking to get FCAT running on a 7680x1440 array ;) 
  • 23 Hide
    timw03878 , April 23, 2013 9:47 PM
    Here's an idea. Take away the 8 games at 40 bucks a piece and deduct that from the insane 1000 price tag.
  • 12 Hide
    17seconds , April 23, 2013 9:37 PM
    Sort of seems like a mess to me. The game bundle is nice.
Other Comments
  • 12 Hide
    whyso , April 23, 2013 9:36 PM
    Power usage?

    Thats some nice gains from the prototype driver.
  • 12 Hide
    17seconds , April 23, 2013 9:37 PM
    Sort of seems like a mess to me. The game bundle is nice.
  • 23 Hide
    timw03878 , April 23, 2013 9:47 PM
    Here's an idea. Take away the 8 games at 40 bucks a piece and deduct that from the insane 1000 price tag.
  • 10 Hide
    cangelini , April 23, 2013 9:51 PM
    whysoPower usage?Thats some nice gains from the prototype driver.

    Power is the one thing I didn't have time for. We already know the 7990 is a 375 W card, while GTX 690 is a 300 W card, though. We also know AMD has Zero Core, which is going to shave off power at idle with one GPU shut off. I'm not expecting any surprises on power that those specs and technologies don't already insinuate.
  • -4 Hide
    ASHISH65 , April 23, 2013 9:51 PM
    nice article! here comes the Competitor of gtx 690!
  • 26 Hide
    cangelini , April 23, 2013 9:53 PM
    donquad2001this test was 99% useless to the average gamer,Test the card at 1900x1080 like most of us use to get a real ideal of what its like,only your unigine benchmarks helped the average gamer,who cares what any card can do at a resolution we cant use anyway?

    If you're looking to game at 1920x1080, I can save you a ton of money by recommending something less than half as expensive. This card is for folks playing at 2560 *at least.* Next time, I'm looking to get FCAT running on a 7680x1440 array ;) 
  • 2 Hide
    hero1 , April 23, 2013 9:54 PM
    Nice article. I was hopping that they would have addressed the whining but they haven't and that's a shame. Performance wise it can be matched by GTX 680 SLI and GTX 690 without the huge time variance and runt frames. Let's hope they fix their whining issue and FPS without forcing users to turn on V-sync. For now I know where my money is going consider that I have dealt with AMD before:XFX and Sapphire and didn't like the results (whining, artifacts, XF stops working etc). Sorry but I gave the red team a try and I will stick with Nvidia until AMD can prove that they have fixed their issues.
  • 1 Hide
    ohim , April 23, 2013 10:02 PM
    Why are all you people, that this card is not made for, complain about the price tag? AMD / Nvidia for sure don`t really make a profit if any out of these monsters. They are just for show like in the CPU business.
    People mostly buy Intel (I3/i5 a lot more than i7) just because Intel can provide top of the line CPUs in the i7 Extreme range. Same goes here, if some hears that AMD has a better 1000$ card than Nvidia, they will probably spend 100-200$ for an AMD card and not Nvidia.
    Power ... unless you`re not a guy who saves 2 years in a row for this card to have a 6 months nerd gaming glory you won`t care that much how power hungry this card is.

    Is just like asking Ferrari or Lamborghini how many mpg their cars do.
  • 6 Hide
    mayankleoboy1 , April 23, 2013 10:14 PM
    1.I wonder if inserting all those pauses in the rendering pipeline for smoothness harms the compute performance.

    2. Regarding the fan noise and the hum : It would be interesting to know how much noticable is the fan noise and the hum with increaseing listner distance. IOW, which noise is more noticable at near/medium/far distances ?


    Drivers still are AMD's biggest weakness. I would have expected AMD to havetop-notch , A-one drivers to go with the HD7990. After all, this is AMD's halo product. The first impression is what matters. The conclusion is basically "Card is good. Drivers are poor, with better coming in future". So ultimately its selling a promise, which may/may not succeed. It appears to me that AMD doesnt value its own products.
  • -1 Hide
    mayankleoboy1 , April 23, 2013 10:18 PM
    Ohh, and a video conversion test would have been nice too. (Is there any software available that supports CFX ?)
    Also, has the Video Conversion Engine in AMD taken off ?
  • 0 Hide
    jezus53 , April 23, 2013 10:26 PM
    It's very interesting that AMD couldn't find a capacitor that wouldn't cause this noise. I feel once third party vendors get the reference they'll find ways of removing that. Hope they fix it soon or else nVidia will have a new line of cards while AMD is having problems with neatly two year old chips!!!
  • 1 Hide
    dragonsqrrl , April 23, 2013 10:41 PM
    hero1Nice article. I was hopping that they would have addressed the whining but they haven't and that's a shame. Performance wise it can be matched by GTX 680 SLI and GTX 690 without the huge time variance and runt frames. Let's hope they fix their whining issue and FPS without forcing users to turn on V-sync. For now I know where my money is going consider that I have dealt with AMD before:XFX and Sapphire and didn't like the results (whining, artifacts, XF stops working etc). Sorry but I gave the red team a try and I will stick with Nvidia until AMD can prove that they have fixed their issues.

    Unfortunately I'm really not sure the whining issue is something that can be fixed with a driver update. I think it has more to do with the hardware on the board than anything else. But it's good to see that AMD has finally recognized the frame time variance and micro-stutter problem, and are actively pursuing a solution. Although the test in the review was limited, I think it's telling that every gamer tested was able to recognize the difference between AMD and Nvidia cards, and even the difference brought by AMD's own prototype drivers.
  • 2 Hide
    hero1 , April 23, 2013 10:51 PM
    dragonsqrrlUnfortunately I'm really not sure the whining issue is something that can be fixed with a driver update. I think it has more to do with the hardware on the board than anything else. But it's good to see that AMD has finally recognized the frame time variance and micro-stutter problem, and are actively pursing a solution. Although the test in the review was limited, I think it's telling that every gamer tested was able to recognize the difference between AMD and Nvidia cards, and even the difference brought by AMD's own prototype drivers.


    I know and that's what I meant by hopping that they would have addressed the whining with this card. It happens to all their cards, well the ones that I have owned especially the XFX and if they knew what causes then they should have fixed it.

    Let's hope that the prototype driver will also translate to better drivers for all their GPUs and address the frame rate issues. Other than that, it is a good card but I think, for my personal use since I was waiting to see what this can offer, I will just get the GTX 680 or the GTX 780 next month and will definitely go back to AMD if they address those issues.
  • 2 Hide
    dragonsqrrl , April 23, 2013 10:54 PM
    whysoPower usage?Thats some nice gains from the prototype driver.


    For everyone seeking power and heat results:
    http://www.anandtech.com/show/6915/amd-radeon-hd-7990-review-7990-gets-official/16

    It consumes a lot of power under load, substantially more than the GTX690, but like Chris said that's to be expected. The big difference with the 7990 seems to be acoustics in relation to temps at load. It's a massive improvement over the 6990, and pretty much on par with the GTX690. Unfortunately the coil whine seems to undo a lot of the improvements made to the stock cooler, but all things considered it's pretty impressive what AMD was able to do in this area, especially in comparison to unofficial solutions from other vendors (dual slot, only requires 2 8-pin).
  • 2 Hide
    dragonsqrrl , April 23, 2013 10:57 PM
    hero1I know and that's what I meant by hopping that they would have addressed the whining with this card.

    Sorry, that's a reading fail on my part. Thought you said, 'hope they'll address the whining' or something to that effect.
  • 2 Hide
    hero1 , April 23, 2013 11:00 PM
    dragonsqrrlSorry, that's a reading fail on my part. Thought you said, 'hope they'll address the whining' or something to that effect.


    No problem.
  • 5 Hide
    bartholomew , April 23, 2013 11:32 PM
    A Price tag of $849.99 would had been quite aggressive & increased its value significantly.
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