Sapphire HD 7970 6GB Toxic Edition Review

ccokeman - 2012-07-13 18:15:02 in Video Cards
Category: Video Cards
Reviewed by: ccokeman   
Reviewed on: July 16, 2012
Price: $680


Almost a month ago the HD 7970GHz edition cards were introduced, bringing along all the enhancements inherent with a maturation of the manufacturing process. Most notable was higher clock speeds hence the GHz Edition moniker. The Sapphire HD 7970 6GB Toxic Edition is built upon this improved process silicon. Not content to deliver a card based on the reference design, Sapphire has thrown away the book and put together its own design using a custom 12 layer PCB, double sided Black Diamond chokes and DirectFET technology; all part of its Lethal Power Suite. Cooling is via an all new Vapor-X implementation designed for this card to manage the thermals while keeping noise in check with new 90mm fans.

The stock GHz Edition cards from AMD have 1000MHz clock speed with a boost clock of 1050MHz, with the memory a constant 1500MHz. Compared to the standard HD 7970 clocks of 925MHz on the core and 1375MHz on the memory there is a significant boost in clock speed and ergo, performance. Sapphire has upped the ante with clock speeds of 1050MHz with a boost clock of 1100MHz or 50MHz higher than the standard GHz Edition. Memory speeds are constant at 1500MHz. How does it get better than that? Sapphire has added the Lethal Boost button to bump the clock speeds even higher to 1150MHz with a boost clock of 1200MHz and 1600MHz on the memory using AMD's Power Tune feature. Pricing will of course be higher than a reference version at around $680 but you get a full custom design that should offer improved stability and cooling long term. Let's see what the Sapphire HD 7970 Toxic Edition has to offer.

Closer Look:

Image has always been something that Sapphire uses to effect. With the latest offering in the Toxic line up we have a futuristic rendition of Ruby based soley on the unmistakable female figure. Highlights on the front panel include the fact that this is a GHz Edition card in Sapphire's line up. The list of features include the Lethal Power Suite, Lethal Boost button and Vapor-X cooling solution, a massive 6GB of GDDR5 memory and support for CrossfireX, Eyefinity, and the 28nm GCN architecture. The back side delves into the details of the feature set including AMD HD3D, AMD APP acceleration and more.












Inside the outer sleeve is a plain box that holds the HD 7970 6GB Toxic Edition. It is split into two levels with the top level holding the card in a formed cardboard shell while the lower level holds the accessory bundle in a separate box. Pretty much standard packaging from Sapphire. If it works why change.


The bundle included with the Sapphire HD 7970 6GB Toxic Edition contains all the parts necessary to get the card installed in just about any configuration with an HDMI cable, DVI to VGA adapter, Mini-DP to DP adapter, two dual 4-pin to 6-pin PCIe power adapters, Mini-DP to DVI active adapter, quick start guide, Lethal Boost button instructions and a registration guide with a link to Sapphire's free TriXX overclocking utility.


Packaging and accessories do not begin to tell the entire story of the Toxic Edition HD 7970 so let's take a look a little deeper into what Sapphire has done with this improved offering in its HD 7900 series product stack.

Closer Look:

Sapphire's latest HD 7970, the 6GB Toxic Edition, is built upon the GHz Edition 28nm GCN "Tahiti" Core from AMD. Just by looks alone you can tell that this card is far from a reference design card from the black 12 layer PCB to the large dual fan equipped Vapor-X cooling solution and Lethal Power Suite VRM design. At 11 inches in length, the HD 7970 6GB Toxic Edition should not provide any fitment issues in most mid tower or larger cases. The 11 inch card hangs over the motherboard PCB by about 1/8th of an inch on a full size ATX form factor motherboard. From the top you can see that Sapphire implemented a dual fan custom cooling solution with the Toxic logo on each fan while the back side has the Vapor-X logo on the back plate used to dissipate the thermal load from the 3GB of memory on the back side of the PCB. The opening on the back is used to clear part of the Lethal Power Black Diamond chokes. The side views give a glimpse of the four heat pipe cooling solution and shroud. The Sapphire logo is lit with a white LED and is visible when the card is powered on and in operation. This card is built to work within the PCIe 3.0 specification with motherboards that support the specification.















Connectivity on the HD 7970 6GB Toxic Edition is much like what you would find on one of Sapphire's Flex Edition cards with a pair of Dual Link DVI ports, an HDMI 1.4a port and a pair of Mini DisplayPort 1.2 ports. By using an MST hub or daisy chaining DisplayPort monitors you can get up to six displays in an Eyefinity setup out of the pair of Mini DP ports. Eyefinity 2.0 brings along the ability to have independent audio streams for each video so you can have independent video streams with audio that follows along with it. Venting on the mounting bracket is compromised somewhat by the second DVI port but it looks like Sapphire opened up all possible avenues for airflow. The rear of the card is open to vent out the thermals from the card. Both of the fans used on the cooling solution are plugged into separate headers on the PCB.


Just like the rest of the HD 79XX series the Toxic Edition supports CrossfireX with up to four cards in a supporting motherboard using the dual bridge connections. Under the Crossfire bridge connections are a series of LEDs to monitor the temperature of the PCB and report in a visual fashion, Green-Yellow-Red, with the associated common meanings for the LEDs. Past versions of the HD 7970 used a dual BIOS switch to recover from a bad flash or to flash a different BIOS file with higher clock speeds. On the Toxic Edition Sapphire has come up with a different solution that takes away that recovery options but put that second file as the Lethal Boost file that increases the core clock and memory speeds, Power Tune settings and loads a fan profile to compensate for the higher clocks and voltage levels. When enabled the button turns blue to show the profile is enabled. On this card the clock speeds will see maximums of 1200MHz on the "Tahiti" core and 1600MHz on the 6GB of memory. This is a significant boost with just a button push. I found this button to work as advertised with a boost in 3DMark 11 performance of over 500 points using the performance preset. Dual 8-pin power connections are used to supply the current demands of the Toxic Edition HD 7970 with a 375 watt draw possible via the power connections and PCIe slot.


Pulling the card apart shows the custom layout and Lethal Power Suite power design. The cooling solution comes off with four screws while the back plate is held in place by many more. The heat sinks on the VRM circuits are held to the back plate for a much more secure mount than push pins can offer. The front of the PCB and back of the PCB have significant elements of the Lethal Power Suite 8+1+1 power circuits.


Sapphire uses an 8+1+1 power circuit called Lethal Power Suite that includes an 8+1+1 phase power circuit running through a 12 layer PCB. Eight phases feed power to the CPU core with another dedicated to the memory and MVDD circuit. Used in this implementation are new double sided Black Diamond chokes and DirectFET technology that work to reduce operating temperatures of this part of the system by as much as 40 °C. Additional cooling comes by way of small heat sinks attached to the PCB. Under the small blue cover above the eight phase power circuit are what looks like a series of voltage check points that could prove useful for the extreme overclocker.


The cooling solution used on the Sapphire HD 7970 6GB Toxic Edition is a dual 90mm fan cooled vapor chamber and heat pipe-equipped solution. The shroud mounts over the heat sink assembly for easy removal. What Sapphire has put together is a new Vapor-X vapor chamber designed specifically for this card. The vapor chamber has a stepped surface to mate with the core due to the shim around the core. Four heat pipes in total pull the thermal load away form the vapor chamber and carry it to the fin array. Two of the heat pipes are 8mm in size with two at 6mm. A pair of small aluminum sinks cool the power circuits and fit under the main thermal solution.


Dual fans are used on the thermal solution on the Toxic Edition. These fans made by FirstD are 90mm in size, PWM controlled, and feature an aerofoil fin design and hubs that are designed to be dust resistant, improving longevity of both the fans and the card. When run at maximum speed the fans are audible in the case depending on the fan speed used. While PWM controlled they were incredibly quiet by contrast to a reference cooling solution.


Lastly we get to the GPU core and memory. The GHZ edition 28nm Tahiti core is just an improved process core that features the same GCN architecture and specifications for the most part. Transistor count stays at 4.31 billion, the stream processor count stays at 2048, texture units at 128, ROPs stay at 32. GDDR5 memory is used but the capacity on this card increases to 6GB from 3GB, but still running on a 384-bit bus. Where this core gets its performance chops is from the increase in base clock speeds on the core and memory. Sapphire bumped up the clock speeds from 1000/1050MHz on the reference GHz Edition card to 1050/1100MHz on the Toxic with a boost to 1150/1200MHz using the Lethal Boost feature. Twenty-four Hynix GDDR5 modules with part number H5GQ2H24AFR-R0C are used to make up the massive and industry first 6GB frame buffer and are rated to run at 1500MHz. With the Lethal Boost feature these easily run at 1600MHz. Software based voltage control is available with the use of the CHIL voltage controller.


Seeing how the card is built and all that has been done to improve on the basic design set of the reference card, the Sapphire HD 7970 6GB Toxic Edition is poised to sit atop the HD 7970 performance mountain and ready to play King of the Hill.



2 x Dual-Link DVI
1 x HDMI (with 3D)
2 x Mini-DisplayPort
1100MHz Core Clock
28 nm Chip
2048 x Stream Processors
6144 MB Size
384-bit GDDR5
6000 MHz Effective
275(L) x 115(W) x 42(H) mm
Driver CD
CrossFire™ Bridge Interconnect Cable
DVI to VGA Adapter
Mini-DP to DP adapter
6 PIN to 2x4 PIN Power Cable x 2
Mini-DP to DVI active adapter
HDMI 1.4a high speed 1.8 meter cable





All information provided Courtesy of Sapphire @


Testing of the Sapphire Toxic HD 7970 GHz Edition 6GB will consist of running it and comparison cards through the suite of games and synthetic benchmarks. This will test the performance against many popular competitors. Comparisons will be made to cards of a range of capabilities to show where each card falls on the performance ladder. The games used are some of today's newest and most popular titles, which should be able to provide an idea of how the cards perform relative to each other.

The system specifications will remain the same throughout the testing. No adjustment will be made to the respective control panels during the testing, with the exception of the 3DMark 11 testing, where PhysX will be disabled in the NVIDIA Control Panel, if applicable. I will first test the cards at stock speeds, and then overclocked to see the effects of an increase in clock speed. The cards will be placed in order from highest to lowest performance in each graph to show where they fall by comparison. The NVIDIA comparison cards will be using the 301.42 drivers with AMD cards using the Catalyst 12.4 drivers and latest CAP profile.


Testing Setup:


Comparison Video Cards:




Sapphire has given the end user a few different options to get the highest level of performance out of the Toxic HD 7970 GHz Edition 6GB. Using traditional means with an overclocking utility like Sapphire's own TriXX where manual manipulation of the clock speeds voltages, fan speeds and current overage can all be tweaked to get the absolute highest stable clock speeds. The other option on this card is the Lethal Boost button that loads an overclocked profile once the Lethal Boost button is pushed and the computer restarted to apply the settings. First off let me say that this card delivered the highest clock speeds I have been able to reach on an air cooled HD 7970. Only the water cooled Powercolor HD 7970 LCS comes close. Manually tweaking the card resulted in clock speeds of 1235MHz on the 28nm core and 1735MHz on the 6GB of GDDR5 memory using 1174mv. Pretty stout to say the least on an air cooled card. Using a VDDR higher than 1180mv resulted in serious artifacts rather than the desired result of higher clock speeds. The results were the same when loading the card at both 1920x1080 and 5760x1080. The Toxic HD 7970 is rated at 1050MHz with a dynamic boost to 1100MHz although I never saw less than 1100MHz in my testing. The manual tweaked results equate to increases of just over 12% on the core and just over 15% on the 6GB of GDDR5 memory.

Sure manually tweaking can be rewarding but what about just pushing a button for big clock speeds. At times I'll take the easy button. By using the Lethal Boost button approach the Toxic HD 7970 6GB loads a profile that increases the clock speeds from already high 1100/1500MHz to 1200MHz on the core and 1600MHz on the memory. 1200MHz on the core is a pretty solid result that proves to be fully stable in my testing. That easy button really works delivering significant performance gains over the factory overclocked HD 7970. The cooling used on the Toxic HD 7970 plays a part in delivering these results with temperatures on the core at only 65 °C under load with the fan at 90%. Moving to 100% did not add any overclocking margin so the fan speeds were reduce to cut some of the fan noise. All in all the Toxic HD 7970 GHz Edition delivered a positive experience when it came to overclocking as expected.


Maximum Clock Speeds:

Testing for the maximum clock speed consists of looping Unigine 3.0 for 30 minutes each to see where the clock speeds fail when pushed. If the clock speed adjustment fails, then the clock speeds and tests are rerun until they pass a full hour of testing.



  1. Metro 2033
  2. Batman: Arkham City
  3. Battlefield 3
  4. Unigine Heaven Benchmark 3.0
  5. Sid Meier's Civilization V
  6. DiRT 3
  7. Mafia II
  8. 3DMark 11


  1. Temperatures
  2. Power Consumption


Part first-person shooter, part survival horror, Metro 2033 is based on the novel of the same name, written by Russian author Dmitry Glukhovsky. You play as Artyom in a post-apocalyptic Moscow, where you'll spend most of your time traversing the metro system, with occasional trips to the surface. Despite the dark atmosphere and bleak future for mankind, the visuals are anything but bleak. Powered by the 4A Engine, with support for DirectX 11, NVIDIA PhysX, and NVIDIA 3D Vision, the tunnels are extremely varied – in your travels, you'll come across human outposts, bandit settlements, and even half-eaten corpses. Ensuring you feel all the tension, there is no map and no health meter. Get lost without enough gas mask filters and adrenaline shots and you may soon wind up as one of those half-eaten corpses, chewed up by some horrifying manner of irradiated beast that hides in the shadows just waiting for some hapless soul to wander by.














In Metro 2033, the Sapphire Toxic HD 7970 GHz Edition 6GB, while being the fastest single GPU AMD card in the comparison, is still slower than the GTX 680 at 1920x1080. When you get to 5760x1080 the Toxic HD 7970 shows that it is the fastest single GPU card in the comparison.


Batman: Arkham City is the sequel to Batman: Arkham Asylum released in 2009. This action adventure game based on DC Comics' Batman super hero was developed by Rocksteady Studios and published by Warner Bros. Interactive Entertainment. Batman: Arkham City uses the Unreal 3 engine.

















In this game the Toxic HD 7970 delivers excellent FPS performance by comparison to the factory overclocked Black Edition.


Battlefield 3 is a first-person shooter video game developed by EA Digital Illusions CE and published by Electronic Arts. Battlefield 3 uses the Frostbyte 2 game engine and is the direct successor to Battlefield 2. Released in North America on October 25, 2011, the game supports DirectX 10 and 11.

















In BF3 the Toxic HD 7970 6GB card gives the GTX 680 a run for its money in all four tests. In the three screen tests the Toxic HD 7970 is the faster card.


Unigine Heaven Benchmark 3.0 is a DirectX 11 GPU benchmark based on the Unigine engine. This was the first DX 11 benchmark to allow testing of DX 11 features. What sets the Heaven Benchmark apart is the addition of hardware tessellation, available in three modes – Moderate, Normal and Extreme. Although tessellation requires a video card with DirectX 11 support and Windows Vista/7, the Heaven Benchmark also supports DirectX 9, DirectX 10, DirectX 11 and OpenGL 4.0. Visually, it features beautiful floating islands that contain a tiny village and extremely detailed architecture.
















Again we see that Sapphire's 6GB equipped Toxic HD 7970 is the fastest single GPU card in this test in both 1920x1080 and 5760x1080 resolutions.


Civilization V is a turn-based strategy game. The premise is to play as one of 18 civilizations and lead the civilization from the "dawn of man" up to the space age. This latest iteration of the Civilization series uses a new game engine and massive changes to the way the AI is used throughout the game. Civilization V is developed by Firaxis Games and is published by 2K games and was released for Windows in September of 2010. Testing will be done using actual game play with FPS measured by Fraps through a series of five turns, 150 turns into the game.

















Performance wise the Toxic HD 7970 6GB delivers excellent performance across all four tests.


DiRT 3 is the third iteration of this series. Published and developed by Codemasters, this game uses the EGO 2.0 game engine and was released in the US on PC in May of 2011.

















In DiRT 3 the Toxic HD 7970 6GB does not keep up with the GTX 680 until you get to the three screen testing where the performance between the two cards is within 1 FPS maximum.

Closer Look:


Mafia II is a third-person shooter that puts you into the shoes of a poor, Sicilian immigrant, Vito Scarletta. Vito has just returned home from serving overseas in the liberation of fascist Italy, to avoiding his jail sentence, to finding his family in debt. The debt must be repaid by the end of the week, and his childhood friend, Joe Barbaro, conveniently happens to have questionable connections that he assures will help Vito clear the debt by that time. As such, Vito is sucked into a world of quick cash. Released in North America for PC in August of 2010, the game was developed by 2K Czech, published by 2K, and uses the Illusion 1.3 game engine.














The trending of the Toxic HD 7970 6GB being faster than the GTX 680 in three screen mode is reversed in this game test. The AMD card is faster than the GTX 680 at 1920x1080 but not 5760x1080. Even so it is faster than the lower clocked Black Edition.


3DMark 11 is the next installment in Futuremark’s 3DMark series, with Vantage as its predecessor. The name implies that this benchmark is for Microsoft DirectX 11 and with an unintended coincidence, the name matches the year proceeding its release (which was the naming scheme to some prior versions of 3DMark nonetheless). 3DMark 11 is designed solely for DirectX 11, so Windows Vista or 7 are required along with a DirectX 11 graphics card in order to run this test. The Basic Edition has unlimited free tests on performance mode, whereas Vantage is only allowed for a single test run. The advanced edition costs $19.95 and unlocks nearly all of the features of the benchmark, while the professional edition runs $995.00 and is mainly suited for corporate use. The new benchmark contains six tests, four of which are aimed only at graphical testing; one to test for physics handling and one to combine graphics and physics testing together. The open source Bullet Physics library is used for physics simulation and although not as mainstream as Havok or PhysX, it still seems to be a popular choice.

With the new benchmark, comes two new demos that can be watched, both based on the tests. Unlike the tests, however, these contain basic audio. The first demo is titled "Deep Sea" and involves a few vessels exploring what looks to be a sunken U-Boat. The second demo is titled "High Temple" and presents a location similar to South American tribal ruins with statues and the occasional vehicle around. The demos are simple in that they have no story – they are really just a demonstration of what the testing will be like. The vehicles have the logos of the sponsors MSI and Antec on their sides – the sponsorships helping to make the basic edition free. The four graphics tests are slight variants of the demos. I will use the three benchmark test preset levels to test the performance of each card. The presets are used as they are comparable to what can be run with the free version, so that results can be compared across more than just a custom set of test parameters.












The Toxic HD 7970 just cannot pull the performance numbers the GTX 680 can in this test. It does however prove that it is the fastest AMD based single GPU card in this comparison.


Temperature testing will be accomplished by loading the video card to 100% using Unigine's Heaven Benchmark Version 3.0, with MSI's Afterburner overclocking utility for temperature monitoring. I will be using a resolution of 1920x1200 using 8xAA and a five-run sequence to run the test, ensuring that the maximum thermal threshold is reached. The fan speed will be left in the control of the driver package and video card's BIOS for the stock load test, with the fan moved to 100% to see the best possible cooling scenario for the overclocked load test. The idle test will involve a 20-minute cool-down, with the fan speeds left on automatic in the stock speed testing and bumped up to 100% when running overclocked.














Equipped with the latest revision of Sapphire's award winning Vapor-X technology, the Toxic delivers solid cooling performance numbers.


Power consumption of the system will be measured at both idle and loaded states, taking into account the peak voltage of the system with each video card installed. I will use Unigine's Heaven Benchmark version 2.5 to put a load onto the GPU using the settings below. A 15-minute load test will be used to heat up the GPU, with the highest measured temperature recorded as the result. The idle results will be measured after 15 minutes of inactivity on the system. With dual-GPU setups, the two core temperatures will be averaged.














Power consumption numbers for the Toxic are reduced somewhat but with higher clock speeds, more memory, and dual fans, the card is going to increase the use of power.


All I can say is that Sapphire hit this one out of the park, to use a baseball analogy. The HD 7970 6GB Toxic Edition delivers best in class performance against other HD 7900 series cards in part by way of the incredible clock speeds both stock and overclocked. Clock speeds of greater than 1200MHz on the core and 1600MHz on the memory are not going to be possible without having a good base to start with. Sapphire has the baseline covered with a custom 12 layer PCB and its Lethal power suite design. This design uses an eight phase power delivery system for the GPU core voltage with a separate phase for the VRAM and controller for a good stable flow of current to the card. Additionally, double sided Black Diamond chokes and DirectFET technology are used to reduce the operating temperatures for the power circuits by upwards of 40%.

Cooling the HD 7970 6GB Toxic edition is an all new Vapor-X cooling solution that keeps the 28nm core and the 6GB of onboard memory cool to deliver rock solid performance. Using a four heat pipe design with the cooling solution keeps the card cool at both stock and overclocked settings. When the fan is pushed to 90% the GPU core stays at 54 °C during my overclocked testing; that is overclocked and over volted. At 90% the noise generated by the fans is audible but not so much so that it borders on annoying. The fans used are 90mm in size and use an aerofoil design to improve airflow and manage noise characteristics. Fans slowing down and dying have killed many a video card without the owner even knowing what went south until it is to late. To combat this the fans used on the Toxic Edition have fans that use a dust reeling design to improve fan longevity. It's a small thing but well worth mentioning.

The only downside to a cooling solution like the one employed on the Toxic Edition is that it can increase the temperatures of the components installed in the chassis. Manage the airflow in your case and that concern goes away with the heat. A nice touch on this card is the use of a series of LEDs on top of the PCB near the mounting bracket that give a visual indicator of the PCB temperature. Green, yellow, and red LEDs work like a stoplight to let you know all is well and when the card can be ramped up. In testing the Toxic Edition HD 7970, I never saw anything other than a series of green and at most a single yellow when really cranking on the voltage showing the indicator does what it is supposed to do.

When it came to overclocking this card I was pleased to see the clock speeds of 1235MHz on the core and 1735MHz on the 6GB of memory. The only other HD 7970 I have tested to reach this level was a factory overclocked and water cooled HD 7970; driving the cooling significantly lower while needing more current than I had to use on the Toxic Edition HD 7970. Sapphire added to the feature set on the Toxic Edition with several means of overclocking the card. The first option is the Lethal Boost button that boosts the clock speeds on the core up to a dynamically boosted 1200MHz and 1600MHz on the 6GB of memory. To get this boost in performance all that is required is to push the button and reboot; it could not be simpler. Manually tweaking the card is still an option with Sapphire's own free to download TriXX utility, which was used to generate my overclocked results. Each GPU is going to have variations in clock speed margins and voltage tolerances and in this case the core did better with a lower applied voltage (1174mv) in comparison (1250 to 1300mv) to some others I have worked with. Ultimately this helps keep the card cool under load as the cooling solution is nowhere near overworked.

The performance results with the HD 7970 6GB Toxic Edition are easily well above those of even factory overclocked cards I have tested including the comparison cards in this review. At times this puts it right into the realm of the performance envelope delivered by the NVIDIA GTX 680, especially at a resolution of 5760x1080, which really is where this card is designed to shine with the 6GB frame buffer. There was not a single game tested that the HD 7970 6GB Toxic Edition could not handle at "Eyefinity" resolutions with a good bit of the eye candy turned on. Just what the gamer with three screens wants. The bundle of accessories included with the card will allow three screen gaming without having to purchase a Mini DP to DVI active adapter as it part of the bundle. Just one less impediment to getting started.

The Sapphire HD 7970 6GB Toxic Edition is a limited edition card built upon the AMD HD 7970 GHz Edition specification, but pushed to the upper end of the spectrum; both in price (estimated at $680) and in performance delivered. I have to say I was impressed with what Sapphire has brought to the table with this card. After looking at many of its past special edition cards, this one lives up to the heritage of the Atomic and Toxic series and extends the performance legacy cultivated by Sapphire.