The AMD Radeon HD 7990 6GB Arrives


The AMD Radeon HD 7990 6GB dual-GPU behemoth is finally here. We've been talking about the AMD Radeon HD 7990 for years, so to finally see AMD release a card is exhilarating and saddening at the same time. This card is the culmination of years of work and likely marks the pinnacle of the AMD Radeon HD 7000 series of GPUs. Then again it's also likely the fastest AMD Radeon HD 7000 series card to ever be released by AMD. The AMD Radeon HD 7990 was designed from inception to be a juggernaut and to challenge any and all discrete graphics cards on the market. This video card has 4096 stream processors, 6GB of GDDR5 memory, 8.6 billion transistors, 576.0GB/s of memory bandwidth and 8.2 TFLOPS of compute power. This card doesn't command respect, it earns it! AMD also says that it is the world's fastest graphics card, so you shouldn't be shocked to learn that it features a nail-biting, second mortgage inducing price tag of $999.


The AMD Radeon HD 7990 goes by the codename Malta and features a pair of Tahiti XT2 GPU cores that operate at 1000MHz and 6GB of GDDR5 memory running at 6000MHz. These cores are not brand new, but they are the best GPU AMD has to offer and you are getting two of them on one board. This GPU is used on the AMD Radeon HD 7970 GHz Edition card, so you get AMD's 28nm Graphics Core Next (GCN) architecture with all the bells and whistles. AMD had to reduce the core clock by 50MHz versus the single GPU card to keep the power draw and temperatures down, but this is just a minor drop. AMD was able to leave the memory at 6000MHz (effective) though and is why the card has an insane 576GB/s of memory bandwidth.


In order to keep the temperature and noise at bay, AMD developed a radical GPU cooler that features three cooling fans and a each GPU gets a massive heatsink that each has four U-shaped copper heatpipes! The AMD Radeon HD 7990 video cards are part of the Never Settle Reloaded game bundle promotion, so you get a ton of games with this card.  The exact number is eight: BioShock Infinite, Tomb Raider, Crysis 3, Far Cry 3, Far Cry 3 Blood Dragon, Hitman Absolution, Sleeping Dogs and Deus Ex Human Revolution. These games will be included directly in the HD 7990 product box in any region this bundle is available. AMD informed us that the full retail price (not including sales) on these game titles would equate to $334.94! Having eight good game titles coming with the card certainly helps take the bite out of the $999 video card.


The Radeon HD 7790 video card is 12-inches in length and is fairly hefty at 2 pounds and 11 ounces in weight. It looks pretty tough with the three cooling fans and glossy black fan shroud with red accents.


The fan shroud on the AMD Radeon HD 7990 6GB video card is open all the way around, so the hot air is spread out in pretty much all directions. With three fans, this is the only real way to do it due to airflow restrictions and trying to keep the noise levels down.


At each end of the card you can make out the four u-shaped copper heatpipes that help keep the Tahiti XT2 cores that run at 1GHz nice and cool.


For a foot long graphics card having a backplate for reinforcement is a given and here we see that is covers up pretty much everything.


AMD Eyefinity Technology on the AMD Radeon HD 7990 allows the option to expand a single monitor desktop all the way up to five displays at once on a single HD 7990 thanks to the dual-link DVI and four mini-DisplayPort video outputs. The nice thing about the rear bracket on this card is that half of it is open for ventilation!


Here we see the AMD Radeon HD 7990 6GB 'Malta' video cards pair of 8-pin PCI Express power connectors that are located along the top of the video card near the end of the PCB. AMD suggests a 1000 Watt or 1kW power supply when running this graphics card.


On a recent visit to AMD we were able to see some bare AMD Radeon HD 7990 video cards and this is an image of what the front of the PCB looks like of this foot long card. You can clearly see the two Tahiti XT2 GPUs and even the PLX PCIe bridge chip that pairs the two together.


AMD is using a PLX PEX8747 PCI-Express 3.0 48-lane bridge chip that is capable of 96GB/s of interGPU bandwidth to keep data flowing between the processors and to the motherboards PCIe 3.0 x16 slot.


Not too much is going on underneath the backplate, but you can see half of the 6GB of Hynix branded GDDR5 memory ICs.

Now we can get to testing since we know what the AMD Radeon HD 7790 is and more about the Gigabyte and Sapphire retail cards!

Test System

Before we look at the numbers, let's take a brief look at the test system that was used. All testing was done using a fresh install of Windows 7 Ultimate 64-bit and benchmarks were completed on the desktop with no other software programs running.

Video Cards & Drivers used for testing:

Intel X79/LGA2011 Platform

NVIDIA Test Setup

Test System Settings

The Intel X79 platform that we used to test the all of the video cards was running the ASUS P9X79 Deluxe motherboard with BIOS 0305 that came out on 12/25/2012. The Corsair Vengeance 16GB 1866MHz quad channel memory kit was set to 1866MHz with 1.5v and 9-10-9-27 1T memory timings. The OCZ Vertex 3 240GB SSD was run with firmware version 2.25.

The Intel X79 Test Platform






Live Pricing




Intel Core i7-3960X



ASUS P9X79 Deluxe



16GB Corsair 1866MHz


Video Card




Solid-State Drive


OCZ Vertex 3 240GB




Intel RTS2011LC


Power Supply

Corsair AX1200


Operating System


Windows 7 Ultimate 64-bit

AMD Radeon HD 7790 'Malta' Video Card GPU-Z Information:



Batman: Arkham City

Batman: Arkham City PC Game

Batman: Arkham City is a 2011 action-adventure video game developed by Rocksteady Studios. It is the sequel to the 2009 video game Batman: Arkham Asylum, based on the DC Comics superhero Batman. The game was released by Warner Bros. Interactive Entertainment for the PlayStation 3, Xbox 360 and Microsoft Windows. The PC and Onlive version was released on November 22, 2011.

Batman: Arkham City Game Settings

Batman: Arkham City Game Settings

Batman: Arkham City uses the Unreal Engine 3 game engine with PhysX. For benchmark testing of Batman: Arkham City we disabled PhysX to keep it fair and ran the game in DirectX 11 mode with 8x MSAA enabled and all the image quality features cranked up. You can see all of the exact settings in the screen captures above.


Benchmark Results: The NVIDIA GeForce GTX Titan and GeForce GTX 690 were faster at 1920x1080, but at 2560x1600 the AMD Radeon HD 7990 was able to pull ahead of the GeForce GTX 690 by 5 FPS or 5.6%.

Battlefield 3

Battlefield 3 Screenshot

Battlefield 3 (BF3) is a first-person shooter video game developed by EA Digital Illusions CE and published by Electronic Arts. The game was released in North America on October 25, 2011 and in Europe on October 28, 2011. It does not support versions of Windows prior to Windows Vista as the game only supports DirectX 10 and 11. It is a direct sequel to 2005's Battlefield 2, and the eleventh installment in the Battlefield franchise. The game sold 5 million copies in its first week of release and the PC download is exclusive to EA's Origin platform, through which PC users also authenticate when connecting to the game.

Battlefield 3 Screenshot

Battlefield 3 debuts the new Frostbite 2 engine. This updated Frostbite engine can realistically portray the destruction of buildings and scenery to a greater extent than previous versions. Unlike previous iterations, the new version can also support dense urban areas. Battlefield 3 uses a new type of character animation technology called ANT. ANT technology is used in EA Sports games, such as FIFA, but for Battlefield 3 is adapted to create a more realistic soldier, with the ability to transition into cover and turn the head before the body.


Benchmark Results: The NVIDIA GeForce GTX 690 and the AMD Radeon HD 7990 were performing very close in Battlefield 3 at 1920x1080 and 2560x1600.  The ASUS ARES II 6GB card was still the card to beat though!

Borderlands 2

Borderlands 2

Borderlands 2 is a space western first-person role-playing shooter video game that was developed by Gearbox Software and published by 2K Games. It is the sequel to 2009's Borderlands and was released for the Microsoft Windows, PlayStation 3 and Xbox 360 platforms. Borderlands 2 was developed by Gearbox Software and published by 2K Games on September 18, 2012 in North America.

Borderlands 2 Image Quality Settings



Borderlands 2 runs on a heavily modified version of Epic Games' Unreal Engine 3. We tested Borderlands 2 with vSync and depth of field disabled. We increased the general image quality settings and turned on 16x AF. PhysX effects were set to low to keep things fair as possible between AMD and NVIDIA cards.  FXAA was enabled.


Benchmark Results: The NVIDIA GeForce GTX 690 led the pack in Borderlands 2, but the difference between it and the the ASUS ARES II and AMD Radeon HD 7990 were super duper close.


Dirt: Showdown

Image Description

Dirt: Showdown is a video game published and developed by Codemasters for Microsoft Windows, Xbox 360 and PlayStation 3. It was released in May 2012 in Europe and in June in North America. It is part of the Colin McRae Rally game series.

Dirt Showdown Settings
Dirt Showdown Settings

Dirt: Showdown removes several of the gameplay modes featured Dirt 3, and introduces new ones. Gameplay modes can be classified as Racing, Demolition, Hoonigan or Party. We ran the built in Benchmark at Ultra settings to get a true feel of what this engine has to offer!

It is very important to note that Global Illumination and Advanced Lighting have massive performance penalties when enabled, something not seen in other titles in the Dirt series. We disabled this setting.


Benchmark Results: The AMD Radeon HD 7990 pulled ahead of the ASUS ARES II by just 1-2 FPS at both resolutions. The NVIDIA GeForce GTX 690 and GeForce GTX Titan weren't too far behind though and both were over 100FPS at 2560x1600 with everything cranked up.  All of the cards were able to run this title smoothly with no jitters or issues.

Far Cry 3

Farcry3 Game Screenshot

Far Cry 3 is an open world first-person shooter video game developed by Ubisoft Montreal and published by Ubisoft for Microsoft Windows, Xbox 360 and PlayStation 3. It is the sequel to 2008's Far Cry 2. The game was released on December 4th, 2012 for North America. Far Cry 3 is set on a tropical island found somewhere at the intersection of the Indian and Pacific Oceans.[11] After a vacation goes awry, player character Jason Brody has to save his kidnapped friends and escape from the islands and their unhinged inhabitants.

FarCry 3 Quality Settings

FarCry 3 Video Quality

Far Cry 3 uses the Dunia Engine 2 game engine with Havok physics. The graphics are excellent and the game really pushes the limits of what one can expect from mainstream graphics cards. We set game title to 8x MSAA Anti-Aliasing and ultra quality settings. 


Benchmark Results: The NVIDIA GeForce GTX 690 was found to be 2FPS slower than the AMD Radeon HD 7990 at 2560x1600 in Far Cry 3. Again, these two $999 video cards are pretty damn close! The ASUS ARES II 6GB card with it's 100MHz faster core clock was able to lead the AMD Radeon HD 7990. 

Metro 2033

Metro 2033

Metro 2033 is an action-oriented video game with a combination of survival horror and first-person shooter elements. The game is based on the novel Metro 2033 by Russian author Dmitry Glukhovsky. It was developed by 4A Games in the Ukraine. The game is played from the perspective of a character named Artyom. The story takes place in post-apocalyptic Moscow, mostly inside the metro station where the player's character was raised (he was born before the war, in an unharmed city), but occasionally the player has to go above ground on certain missions and scavenge for valuables.

Metro 2033 Settings

This is another extremely demanding game. Image quality settings were raised to 'Very High' quality with 4x AA and 16x AF. We turned off PhysX and DOF (Depth of Field) for benchmarking.


Benchmark Results: Metro 2033 had the ASUS ARES II up on top again, followed by the AMD Radeon HD 7990 and then the NVIDIA GeForce GTX 690. There was a 22% performance advantage to running the AMD Radeon HD 7990 over the NVIDIA GeForce GTX 690 in this benchmark at 2560x1600. 

Sleeping Dogs

Sleeping Dogs PC game

Sleeping Dogs is a 2012 open world action-adventure video game developed by United Front Games in conjunction with Square Enix London Studios and published by Square Enix. The game was released on August 14, 2012, for Microsoft Windows. The game uses the Havok physics engine.

Sleeping Dogs Extreme Settings

We used the Adrenaline Sleeping Dogs Benchmark tool to benchmark this game title to make sure the benchmarking was consistent. We tested with 'Ultra' quality setting at 1920x1080 and 2560x1600 resolutions.


Benchmark Results: With 'ultra' image quality settings the AMD Radeon HD 7990 was found to be 8.4 FPS or 22% faster than the NVIDIA GeForce GT 690 at 2560x1600.

3DMark 11

Futuremark 3DMark 11 Benchmark

3DMark 11 is the latest version of the world’s most popular benchmark for measuring the 3D graphics performance of gaming PCs. 3DMark 11 uses a native DirectX 11 engine designed to make extensive use of all the new features in DirectX 11, including tessellation, compute shaders and multi-threading.

Futuremark 3DMark 11 Benchmark Settings

We ran 3DMark11 with both the performance and extreme presets to see how our hardware will run.

3DMark11 Performance Benchmark Results:


Benchmark Results: The ASUS ARES II scored P16542 3DMarks, the NVIDIA GeForce GTX 690 scored P15520 3DMarks and the AMD Radeon HD 7790 scored P15520 3DMarks in 3DMark11 with the performance preset. Not bad scores from the $999 and above graphics cards!

3DMark11 Extreme Benchmark Results:


Benchmark Results: When Futuremark 3DMark11 is run with the extreme settings the performance scaling between the test cards is almost linear, which is pretty wild. The AMD Radeon HD 7990 6GB video card was able to score X5839 on 3DMark11 with the extreme preset!.

3DMark 2013

3Dmark Fire Strike Benchmark Results - For high performance gaming PCs

Use Fire Strike to test the performance of dedicated gaming PCs, or use the Fire Strike Extreme preset for high-end systems with multiple GPUs. Fire Strike uses a multi-threaded DirectX 11 engine to test DirectX 11 hardware.

3DMark Fire Strike


Fire Strike Benchmark Results:



Benchmark Results: 3DMark Fire Strike shows that the AMD Radeon HD 7990 to be ahead of the NVIDIA GeForce GTX 690 by a fairly large amount, so there is a big difference in results from the two 3DMark versions. 3DMark Firestrike shows the AMD Radeon HD 7990 to be about 19% faster than the NVIDIA GeForce GTX 690.

Fire Strike Extreme:


Benchmark Results: 3DMark Fire Strike Extreme is a very tough benchmark to run and showed the AMD Radeon HD 7990 to be 17% faster than the NVIDIA GeForce GTX 690.

Power Consumption


For testing power consumption, we took our test system and plugged it into a Kill-A-Watt power meter. For idle numbers, we allowed the system to idle on the desktop for 15 minutes and took the reading. For load numbers we measured the peak wattage used by the system while running the OpenGL benchmark FurMark 1.10.6 at 1024x768 resolution in full screen mode. We also ran four game titles at 1920x1080 and averaged the peak results recorded the highest Wattage seen on the meter for the gaming results.


Power Consumption Results: When it comes to power use the AMD Radeon HD 7990 6GB card did very well at idle thanks to AMD ZeroCore Power Technology. AMD ZeroCore Power Technology is designed to intelligently manage GPU power consumption in response to certain GPU load conditions by clock gating, power gating, memory compression, and a host of other power saving tricks. It also raises and lowers clockspeeds via AMD PowerTune and takes into account application use, system temperature and/or user system configuration. This is one of the reasons that all these high-end graphics cards have such good power numbers at idle!

At full load we noted that the entire system at the wall was pulling 546 Watts in game titles on average, which is about 100 Watts more power than the NVIDIA GeFroce GTX 690. The AMD Radeon HD 7990 6GB was more efficient than the ASUS ARES II as it used nearly 120 Watts less power when gaming. The ASUS ARES II, AMD Radeon HD 7990 and NVIDIA GeForce GTX 690 are all dual-GPU powered cards powered by flagship GPUs, so it shouldn't come as a shock to see them pulling 450W and above when gaming. Just be sure to have a beefy 850W or higher PSU for your system with one of these cards.

Temperature & Noise Testing

Temperatures are important to enthusiasts and gamers, so we took a bit of time and did some temperature testing on the AMD Radeon HD 7790 6GB video card.

AMD Radeon HD 7790 6GB Idle Temperature:


The AMD Radeon HD 7990 video card had an idle temperature of 32.0C in a room that was 22.0C (72F). Not a bad temperature considering this card has 8.6 billion transistors and 4096 cores! Both cores had nearly identical temperatures, so we'll just focus on one core to simplify things.


AMD Radeon HD 7990 6GB in Furmark:


With Furmark fired up and saw temperature reach 75C, but notice that the GPU started throttling. The average GPU core clock is around 700MHz, but was bouncing between 500MHz and 1000MHz constantly.

AMD Radeon HD 7990 6GB Temps in Games: 


In games we found the AMD Radeon HD 7990 6GB graphics card would still reach 75C, but it would do so at 1000MHz core and 1500MHz memory and stay there. Note that we used 3206MB of the frame buffer when gaming at 2560x1600, so we put a good chuck of that frame buffer to good use. The fan speed was right around 2500RPM on the fans when running Furmark and in game titles.


We tossed up the temperature results in a chart and as you can see the AMD Radeon HD 7790 did pretty good when it comes to thermal performance and we have absolutely nothing but good things to say when it comes to temperatures and cooling performance.

Sound Testing

For sound testing we use an Extech sound level meter with ±1.5dB accuracy that meets Type 2 standards. This meter ranges from 35dB to 90dB on the low measurement range, which is perfect for us as our test room usually averages around 36dB. We measure the sound level two inches above the corner of the motherboard with 'A' frequency weighting. The microphone wind cover is used to make sure no wind is blowing across the microphone, which would seriously throw off the data.


When it comes to noise levels the AMD Radeon HD 7990 was pretty quiet at idle, but was fairly loud when at full load. Our results directly contradict what AMD showed internally:


AMD also used Furmark, but this really isn't really a fair comparison against NVIDIA cards as the Radeon HD 7990 is heavily throttled as we just showed you moments ago. We'll replace the battery in our sound meter to double check our scores, but the way we measure sound and our ears tell us at load that the Radeon HD 7990 is a tad louder than the GeForce GTX 690 at full load.

Overclocking The 7990

To take a quick look at overclocking we fired up AMD Catalyst Control Center and used AMD Overdrive to overclock both the mighty AMD Radeon HD 7990 6GB 'Malta' video card.


The AMD Radeon HD 7990 6GB comes clocked at 1000MHz on the core and 1500MHz on the memory. You can go up to 1100MHz on the core and 1575MHz on the memory in AMD OverDrive.


We were easily able to overclock the Radeon HD 7790 to 1100MHz on the core and 1575MHz on the memory. The card was rock solid in games and we tried the power control settings at various percentages with no issues.


Let's take a look at some Futuremark 3DMark11 on the performance preset to see how the overclock helped performance.

AMD Radeon HD 7990 at 1000MHz core and 1500MHz memory:


AMD Radeon HD 7990 at 1100MHz core and 1575Hz memory:


Something isn't right here!  The score went from P15225 to P15242 with a 100MHz overclock on the core? We let AMD know this and the had no answer.

Final Thoughts and Conclusions


The AMD Radeon HD 7990 6GB 'Malta' video card was found to be a beast in every right. The Mediterranean island of Malta is the largest of the three major islands that constitute the Maltese archipelago. Here we have the AMD 7990 being the largest and fastest of the three cards that make up the AMD Radeon HD 7900 series, so the internal codename makes sense. This card also caps of the AMD Radeon HD 7000 series and it was able to showcase the power of the Tahiti XT2 GPU cores and AMD's 28nm GCN technology.


When it comes to performance you really need a 30-inch display running 2560x1600 or a multi-panel AMD Eyefinity setup to get the most out of the Radeon HD 7990. We don't have a 4K display available to test on, but AMD says that the Radeon HD 7990 video card is ready for Ultra HD 4K gaming and provided us with the performance slide above. It shows that the Radeon HD 7990 does a tad better than the NVIDIA GeForce GTX690 in 11 game titles. Our performance testing showed that the AMD Radeon HD 7990 be the NVIDIA GeForce GTX 690 more times than not at 2560x1600. The performance of the AMD Radeon HD 7990 was solid, but we were expecting a bit more from this card for the price. Sure, it beats the NVIDIA GeForce GTX 690 more times than not, but NVIDIA released that card back on May 2nd, 2012. It took AMD basically a year to release a dual-GPU card that could take the performance crown. While we are on the topics of dates did you know that this is AMD's first new dual-GPU card since the AMD Radeon HD 6990 was launched in March 2011? This card has been in the making for a long time and we were told that it was coming over a year ago.


As with all high-end graphics cards they AMD Radeon HD 7990 costs an arm and a leg.  This card will set you back $999, but it comes with eight game titles as part of the bundle that have a full retail value of over $325. This certainly helps offset the price of this card and makes it a compelling reason to purchase this card over the NVIDIA GeForce GTX 690 that it was able to outperform more times than not. We should also mention that we completed our testing with CATALYST 13.5 Beta 2 drivers, but AMD also send over some preview drivers that really help frame latencies and frame pacing performance. A number of sites are showing weakness when it comes to frame latencies and micro stutters on AMD cards, but AMD has taken action and has some software fixes in the works. Legit Reviews hasn't gotten into frame capturing for our video card reviews just yet because we wanted to see how things play out. AMD appears to have a software fix for now and it is safe to assume that future GPU's that aren't taped out will have some new technologies to avoid the stutters. NVIDIA is clearly ahead of the game when it comes to that aspect, but we expect AMD to have a solution and that all could pass. Is it worth a $5,000-$10,000 investment to capture frames and report on something that has a fix in the works? We'll let you tell us!

Legit Bottom Line: The AMD Radeon HD 7990 6GB video card is a monster and takes the dual-GPU performance crown away from NVIDIA and the GeForce GTX 690, but after waiting all this time is it enough?