AMD Radeon HD 7990 6GB Dual GPU Video Card Overclocked

We've tested the new AMD Radeon HD 7990 dual GPU beast with its out of the box performance, and now we see what happens when we overclock it.

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Introduction and Overclocking

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Having already tested the AMD Radeon HD 7990 6GB with its out of the box performance, the next step after that is to check out the overclocking side of things. Performance of the new AMD model is exceptionally strong - with the $999 price tag and the fact it's a dual GPU card, though, we wouldn't expect anything less from it.

There's really not a whole lot that needs to be said from an introduction stand point. We really just finished looking at the HD 7990 6GB and we're going straight into overclocking. What we'll quickly do is talk about the overclocking below before looking at our testbed, the cards that we'll be using in our graphs today before we get into the performance.

Overclocking

Normally we fire up MSI Afterburner to do all our overclocking. Inside we found that we didn't have any voltage adjustment. That was not a huge surprise, though, considering the model has just launched. If we see it in the next few weeks, only time will tell. With that said we went straight into the core clocks to see just what we could get out of the new video card. We pushed the cores up to 1150MHz, but as soon as we started to run 3DMark 11, our system froze.

We rebooted and went back to MSI Afterburner. We then upped the core clocks to 1100MHz. We completed the run with no issue, but the final score was near identical to the default run - it was actually slightly less. Doing a little bit of research I discovered that we weren't the only people to run into this problem.

Moving away from MSI Afterburner we decided to jump into the Catalyst Control Center instead and see if we had any more luck. While we don't have the same kind of range when it comes to clocks, the 1100MHz limitation on the core should be fine, especially when we don't have the ability to adjust the voltage of the core at this stage.

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In the end we had the reference video card running at 1100MHz on the core, up from 1000MHz. The 6GB of GDDR5 was increased from 6000MHz QDR to 6300MHz QDR.

The results were kind of interesting and we'll discuss it in more detail as we go through our graphs. As we mentioned before, though, let's quickly take a moment to look at our testbed and the cards that will be alongside the overclocked HD 7990 6GB here today.

Benchmarks - Test System Setup

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We would like to thank the following companies for supplying and supporting us with our test system hardware and equipment: Intel, ASUS and Corsair.

Today you're going to see all the setups that you saw in our original HD 7990 6GB coverage. That means we've got the HD 7990 6GB running at both stock and overclocked speeds, along with the PowerColor HD 7950 running at over 1100MHz and the AMD HD 7970 GHz Edition.

As for the NVIDIA side we've got the GTX 650 Ti Boost in SLI in two ways - one comes of the form of two reference cards and the other comes from a pair of Gainward cards overclocked to over 1100MHz on each core. We've also got the EVGA GTX TITAN SuperClocked running at its out of the box speed along with the core at 975MHz and finally a pair of them running together in SLI mode.

The FPS Numbers Explained

When we benchmark our video cards and look at the graphs, we aim to get to a certain level of FPS which we consider playable. While many may argue that the human eye can't see over 24 FPS or 30 FPS, any true gamer will tell you that as we climb higher in Frames Per Seconds (FPS), the overall gameplay feels smoother. There are three numbers we're looking out for when it comes to our benchmarks.

30 FPS - It's the minimum number we aim for when it comes to games. If you're not dropping below 30 FPS during games, you're going to have a nice and smooth gaming experience. The ideal situation is that even in a heavy fire fight, the minimum stays above 30 FPS making sure that you can continue to aim easily or turn the corner with no dramas.

60 FPS - It's the average we look for when we don't have a minimum coming at us. If we're getting an average of 60 FPS, we should have a minimum of 30 FPS or better and as mentioned above, it means we've got some smooth game play happening.

120 FPS - The new number that we've been hunting down over recent months. If you're the owner of a 120 Hz monitor, to get the most out of it you want to get around the 120 FPS mark. Moving from 60 FPS / 60 Hz to 120 FPS / 120 Hz brings with it a certain fluidity that can't really be explained, but instead has to be experienced. Of course, if you're buying a 120 Hz monitor to take advantage of 3D, an average of 120 FPS in our benchmark means that in 3D you will have an average of 60 FPS, which again means you should expect some smooth gameplay.

Why are some graphs incomplete?

Adding new game benchmarks is a long, tedious and time consuming task as every video card has to be re-tested in those new benchmarks. Because of that reason we have always just evaluated our benchmark line up every six months. To stay up to date and current with the latest benchmarks and games available, we've changed our approach to adding new benchmarks.

Our benchmark line up will progress and be updated as newer more intensive games with benchmarks comes to light. While this will mean that initially you may only see a single video card in those particular graphs, as the weeks go on and we test more and more video cards, the results will grow quickly. This will help keep our benchmark line up as up to date as possible as we introduce and remove games on a constant basis.

Benchmarks - 3DMark 11

3DMark 11

Version and / or Patch Used: 1.1

Developer Homepage: http://www.futuremark.com

Product Homepage: http://www.3dmark.com/3dmark11/

Buy It Here

3DMark 11 is the latest version of the world's most popular benchmark. Designed to measure your PC's gaming performance 3DMark 11 makes extensive use of all the new features in DirectX 11 including tessellation, compute shaders and multi-threading. Trusted by gamers worldwide to give accurate and unbiased results, 3DMark 11 is the best way to consistently and reliably test DirectX 11 under game-like loads.

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Starting off with 3DMark 11 we can see a decent gain in performance when it comes to both the P and X preset. Unfortunately we can reveal now that these gains aren't consistent throughout our testing.

Let's get into Heaven on the next page to see what's going on.

Benchmarks - Unigine Heaven Benchmark

Unigine Heaven Benchmark

Version and / or Patch Used: 3

Developer Homepage: http://www.unigine.com

Product Homepage: http://unigine.com/press-releases/091022-heaven_benchmark//

New benchmark grants the power to unleash the DirectX 11 potential in the gift wrapping of impressively towering graphics capabilities. It reveals the enchanting magic of floating islands with a tiny village hidden in the cloudy skies. With the interactive mode emerging experience of exploring the intricate world is ensured within reach. Through its advanced renderer, Unigine is one of the first to set precedence in showcasing the art assets with tessellation, bringing compelling visual finesse, utilizing the technology to the full extend and exhibiting the possibilities of enriching 3D gaming.

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Under Heaven you can see a really nice boost in performance at the lower 1680 x 1050 resolution. When we move to 1920 x 1200, though, you can see performance is near identical.

Benchmarks - Phantasy Star Online 2

Phantasy Star Online 2

Version and / or Patch Used: Standalone Benchmark

Timedemo or Level Used: Built in Benchmark

Developer Homepage: http://www.sega.com/?t=EnglishUSA

Product Homepage: http://www.pso2.com/us/html/index.html

Play Phantasy Star Online 2 and experience revolutionary combat in an action-driven, free-to-play multiplayer online RPG from SEGA. Take a journey into an immersive sci-fi fantasy narrative and explore mysterious worlds to unravel their secrets. Join fellow adventurers and fight against the legions of darkness to banish them from the galaxy.

Score explanation: Less than 2000: Please adjust your game settings because the processing load is quite heavy.

2000 through 5000: The game runs fine at the setting, if you have room, you can adjust some settings.

5001+: The game works wonderfully at this setting.

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PSO2 sees a slight boost in performance, but not nearly as much as you'd expect, though, from two cores running 100MHz higher each.

Benchmarks - Lost Planet 2

Lost Planet 2

Version and / or Patch Used: Standalone Benchmark

Timedemo or Level Used: Built in Benchmark - Test A Scene 1

Developer Homepage: http://www.capcom.com/

Product Homepage: http://www.lostplanet2game.com/

Lost Planet 2 is a third-person shooter video game developed and published by Capcom. The game is the sequel to Lost Planet: Extreme Condition which is also made by Capcom, taking place ten years after the events of the first game, on the same fictional planet. The story takes place back on E.D.N. III 10 years after the events of the first game. The snow has melted to reveal jungles and more tropical areas that have taken the place of more frozen regions. The plot begins with Mercenaries fighting against Jungle Pirates. After destroying a mine, the Mercenaries continue on to evacuate the area, in which a Category-G Akrid appears and attacks them. After being rescued, they find out their evacuation point (Where the Category-G appeared) was a set-up and no pick up team awaited them. The last words imply possible DLC additions to the game, "There's nothing to be gained by wiping out snow pirates... unless you had some kind of grudge."

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Lost Planet 2 numbers across the board aren't too bad. You can see a bit of an increase in performance, but nothing major. Fortunately we're dealing with some already very good numbers anyway.

Benchmarks - Just Cause 2

Just Cause 2

Version and / or Patch Used: Latest Steam Update

Timedemo or Level Used: Dark Tower

Developer Homepage: http://www.eidos.com/

Product Homepage: http://www.justcause.com/

Just Cause 2 employs the Avalanche Engine 2.0, an updated version of the engine used in Just Cause. The game is set on the other side of the world from the original Just Cause, on the fictional island of Panau in Southeast Asia. Panau has varied terrain, from desert to alpine to rainforest. Rico Rodriguez returns as the protagonist, aiming to overthrow the evil dictator Pandak "Baby" Panay and confront his former mentor, Tom Sheldon.

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Across the board you can see Just Cause 2 really sees no changes in the FPS. Nothing more than a bit of fluctuation is really seen with the 2560 x 1600 numbers actually being identical.

Benchmarks - F1 2012

F1 2012

Version and / or Patch Used: Latest Steam Update

Timedemo or Level Used: Built in Benchmark

Developer Homepage: http://www.codemasters.com/uk/

Product Homepage: http://www.codemasters.com

In F1 2012 players will feel the unparalleled thrill of becoming a FORMULA ONE driver with a host of new features, wide-ranging technical and gameplay advancements and extensive competitive and co-operative multiplayer components. F1 2012 will feature all of the official teams, drivers and circuits from the 2012 FIA FORMULA ONE WORLD CHAMPIONSHIP, including the debut of the 2012 FORMULA 1 UNITED STATES GRAND PRIX at Austin, Texas and the return of Germany's famous Hockenheim circuit to the calendar.

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F1 2012 we know was hitting a wall at around 115 FPS and you can see that doesn't change here with all resolutions bouncing around that limit.

Benchmarks - Metro 2033

Metro 2033

Version and / or Patch Used: Latest Steam Update

Timedemo or Level Used: Built in Benchmark

Developer Homepage: http://www.4a-games.com/

Product Homepage: http://www.thqnordic.com/

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 Ukraine and released in March 2010 for Microsoft Windows and Xbox 360.[3] In March 2006, 4A Games announced a partnership with Glukhovsky to collaborate on the game.[4] The game was announced at the 2009 Games Convention in Leipzig;[5] a first trailer came along with the announcement.[6] A sequel was announced, currently titled Metro: Last Light.

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Metro 2033 sees no real change across the board with the overclock. We've got an FPS here and there, but overall it's nothing more than a bit of fluctuation.

Benchmarks - Dirt Showdown

Dirt Showdown

Version and / or Patch Used: Latest Steam Update

Timedemo or Level Used: Built in Benchmark

Developer Homepage: http://www.codemasters.com/uk/

Product Homepage: http://www.codemasters.com/uk/dirtshowdown/360/

DiRT Showdown is the new arcade racing game from the team that brought you the award-winning DiRT series, uncaged in 2012. Pick up and play controls combine with electrifying events, frenzied crowds and stunning graphics to deliver high octane, dive in and drive thrills from event one.

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Dirt Showdown also continues the trend with no difference being seen when it comes to overclocking. You can see across the board the numbers are nearly identical.

Benchmarks - Nexuiz

Nexuiz

Version and / or Patch Used: Latest Steam Update

Timedemo or Level Used: Built in Benchmark

Developer Homepage: http://www.alientrap.org/

Product Homepage: http://www.nexuiz.com/

Nexuiz is an Arena First Person shooter coming soon to consoles. Nexuiz is fast paced with extremely competitive game play. IllFonic brings Alientrap Software's Nexuiz to next-gen gaming consoles around the world while staying true to the game play refined over the years through development. IllFonic introduces a new Victorian influenced art style that is simultaneously futuristic and sophisticated. Nexuiz for consoles is powered by CryENGINE 3.

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At 1680 x 1050 Nexuiz sees a bit of a boost, but above that there's no change. Of course our biggest issue with Nexuiz is the simple fact that it can't make use of CrossFire. You can see the Radeon HD 7990 is only just faster than the HD 7970 at two resolutions.

Benchmarks - Sniper Elite V2

Sniper Elite V2

Version and / or Patch Used: Standalone Benchmark

Timedemo or Level Used: Built in Benchmark

Developer Homepage: http://www.rebellion.co.uk/

Product Homepage: http://sniperelitev2.com/us/age.html

Sniper Elite V2 features detailed sniping simulation with advanced ballistics, taking into account gravity, wind, velocity, bullet penetration, aim stability and more. Guaranteed to provide players with the most realistic simulation of military sharpshooting yet available.

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Sniper Elite V2 sees this massive boost at 1680 x 1050, but after that the numbers are pretty much in line with the stock performance.

Benchmarks - Sleeping Dogs

Sleeping Dogs

Version and / or Patch Used: Latest Steam Update

Timedemo or Level Used: Built in Benchmark

Developer Homepage: http://eu.square-enix.com/en

Product Homepage: http://www.sleepingdogs.net/

The core gameplay of Sleeping Dogs consists of giving the player an open world environment in which to move around freely. Sleeping Dogs is played as an over-the-shoulder, third-person perspective action-adventure game with role-playing elements. The player controls Wei Shen, a Chinese-American police officer, as he goes undercover to infiltrate the Sun On Yee Triad organization. On foot, the player character has the ability to walk, run, jump, climb over obstacles and swim, as well as use weapons and martial arts in combat. Players also drive a variety of vehicles including cars, boats, and motorcycles.

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Sleeping Dogs also follows the trend of seeing no real change when it comes to overclocking. There's a little bit of fluctuation, but that's really about it.

Benchmarks - Far Cry 2

Far Cry 2

Version and / or Patch Used: 1.01

Timedemo or Level Used: Ranch Long

Developer Homepage: http://www.ubi.com/

Product Homepage: http://www.farcry2.com/

Buy It Here

The Dunia Engine was built specifically for Far Cry 2 by the award-winning Ubisoft Montreal development team. It delivers the most realistic destructible environments, amazing special effects such as dynamic fire propagation and storm effects, real-time night-and-day cycle, dynamic music system, non-scripted enemy A.I. and so much more.

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Far Cry 2 performance while still very strong is a little all over the place when it comes to the numbers it's put out. Still, the numbers are massive, so we're not too worried. Nonetheless the consistency when it comes to overclocking is extremely frustrating.

Benchmarks - Hitman Absolution

Hitman Absolution

Version and / or Patch Used: Latest Steam Update

Timedemo or Level Used: Built in Benchmark

Developer Homepage: http://www.ioi.dk/

Product Homepage: http://hitman.com/

Hitman: Absolution is an action-adventure stealth game developed by IO Interactive and published by Square Enix. It is the fifth entry in the Hitman game series, and runs on IO Interactive's proprietary Glacier 2 game engine. Before release, the developers stated that Absolution would be easier to play and more accessible, while still retaining hardcore aspects of the franchise. The game was released on 20 November 2012, which is in the 47th week of the year (in reference to the protagonist, Agent 47).

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1680 x 1050 and 1920 x 1200 sees that performance is at that 68 FPS / 85 FPS wall that we saw at the out of the box speeds. The problem is when we move to 2560 x 1600, the minimum is pretty much at the same point, but we lose 10% off the average. 66 / 77 FPS is still a very good result, but the negative performance is a bit painful.

Benchmarks - Tomb Raider

Tomb Raider

Version and / or Patch Used: Latest Steam Update

Timedemo or Level Used: Built in Benchmark

Developer Homepage: http://www.nixxes.com/

Product Homepage: http://www.tombraider.com/us/base/agegate?refer=184&

Tomb Raider is an action-adventure platform video game. Published by Square Enix, Tomb Raider is the fifth title developed by Crystal Dynamics in the Tomb Raider franchise. As the first entry in a new Tomb Raider continuity, the game is a reboot that emphasizes the reconstructed origins of the culturally influential lead character Lara Croft. Tomb Raider was released on 5 March 2013 for PlayStation 3, Xbox 360 and Microsoft Windows to universal critical acclaim.

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Tomb Raider falls into this category where performance drops back with the overclock in place.

Benchmarks - BioShock Infinite

BioShock Infinite

Version and / or Patch Used: Latest Steam Update

Timedemo or Level Used: Built in Benchmark

Developer Homepage: http://irrationalgames.com/

Product Homepage: http://www.bioshockinfinite.com

BioShock Infinite is a first-person shooter video game and the third installment in the BioShock series. Previously known as "Project Icarus", it is being developed by Irrational Games and was released worldwide on the Microsoft Windows, PlayStation 3, and Xbox 360 platforms on March 26, 2013. BioShock Infinite is not part of the storyline of previous BioShock games but features similar gameplay concepts and themes.

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The negative results under BioShock is no doubt one of the most disappointing as we see the 2560 x 1600 FPS number drop to below 60 FPS - exactly what we don't want to see!

Benchmarks - High Quality AA and AF

High Quality AA and AF

While we test all our games with maximum in-game settings, turning on Anti-Aliasing (AA) and Antistrophic Filtering (AF) helps take the intensity of our testing to another level.

Here we see video cards go from playable FPS to an unplayable FPS and the real power houses continue to help break that 60 FPS mark we always aim for to provide a smooth gaming experience.

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Under our AA and AF tests we can see that performance has dipped back slightly. Of course the numbers are still very strong, and the game remains very playable.

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Metro sees a slightly bump at both resolutions, but nothing spectacular. Considering the 100MHz increase on both cores, we'd expect to see more than just a couple of FPS increase.

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Just Cause 2 performance remains pretty much unchanged when it comes to overclocking.

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Sleeping Dogs sees a couple of extra FPS at 1920 x 1200 and no change at 2560 x 1600.

Temperature Test

The temperature of the core is pulled from MSI Afterburner with the max reading used after a completed run off 3DMark Vantage and the Performance preset.

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Temperature of the video card pretty much remains unchanged. Considering there's no voltage change, this is what we expected.

Sound Test

Pulling out the TES 1350A Sound Level Meter we find ourselves quickly yelling into the top of it to see how loud we can be.

After five minutes of that we get a bit more serious and place the device two CM away from the fan on the card to find the maximum noise level of the card when idle (2D mode) and in load (3D mode).

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Noise levels are slightly elevated, but they're not up enough that you'd actually notice the change.

Power Consumption Test

Using our PROVA Power Analyzer WM-01 or "Power Thingy" as it has become quickly known as to our readers, we are now able to find out what kind of power is being used by our test system and the associated graphics cards installed. Keep in mind; it tests the complete system (minus LCD monitor, which is plugged directly into AC wall socket).

There are a few important notes to remember though; while our maximum power is taken in 3DMark06 at the same exact point, we have seen in particular tests the power being drawn as much as 10% more. We test at the exact same stage every time; therefore tests should be very consistent and accurate.

The other thing to remember is that our test system is bare minimum - only a SSD hard drive is used with a single CD ROM and minimal cooling fans.

So while the system might draw 400 watts in our test system, placing it into your own PC with a number of other items, the draw is going to be higher.

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As you'd expect power draw is up at both load and idle. It's nothing too major, and like we've mentioned a few times now, if you're using a video card like this, you should own or be buying a decent quality, high-wattage power supply at the same time.

Final Thoughts

What we're seeing today with AMD Radeon HD 7990 overclocking is really disappointing and there really seems little reason why performance would be impacted in such a negative way in some areas. Performance is really all over the place from strong gains, to no change, and to a general chunk of FPS being taken off sometimes.

Looking over reviews from other websites what we've noticed is that some have picked up on it and some haven't. Because we've always made overclocking a separate article, we've always looked at how the overclock impacts performance on a much larger scale. You can see that if you test under the right situation overclock brings with it a big boost in performance, in another area you might see no change or a negative impact, especially if you only test one game, like some other websites do.

There's clearly something going on with the overclocking side of things and we've reached out to AMD about it. This is of course something we'll be keeping a close eye on and it's something that we'll re-test when a fix comes to light, as surely AMD are working on it now. It's something that AMD really need to fix, especially if they intend to start attacking some records in the coming weeks, with extreme overclockers around the world. It may be nothing more than a driver update required, but we'll have to play the waiting game a little.

On a whole our opinion on the model really remains unchanged and we absolutely love what AMD has done with the new dual GPU video card. Overclocking is naturally something that you'll want to avoid at the moment, based on what we've seen here today. As we get a chance to see what partners do with the new model, it will be interesting to see if a pre-overclocked model comes to light soon. With the way performance is when overclocking at the moment, we aren't too sure what's going to happen at this stage.

All in all though, the HD 7990 6GB continues to be an absolute beast of a video card and it's no doubt an attractive option for anyone who wants a seriously fast video card, with the money to back that desire. With the way the results have gone today, though, we can't deny the appeal to single GPU options which tend to be nearly flawless when it comes to overclocking.

NVIDIA and the GTX TITAN continues to be very safe at the ultra-high end bracket. AMD have some work to do when it comes to Radeon HD 7990 overclocking.

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Shawn takes care of all of our video card reviews. From 2009, Shawn is also taking care of our memory reviews, and from May 2011, Shawn also takes care of our CPU, chipset and motherboard reviews. As of December 2011, Shawn is based out of Taipei, Taiwan.

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