Faster Than Radeon HD 6970: Sapphire Radeon HD 6950 2 GB Toxic Edition

This is the story of the fastest Radeon HD 6950 graphics card that turned out not only faster than its fellow HD 6950 products, but even faster than the top-of-the-line Radeon HD 6970.

by Sergey Lepilov
08/31/2011 | 10:21 AM

It’s no secret that the Radeon HD 6950 graphics card is far more popular among computer enthusiasts than its elder cousin Radeon HD 6970. The explanation is simple. By reflashing the BIOS of a reference HD 6950 you can get a full-featured HD 6970 for less money. Although a reflashed HD 6950 is often unable to work at the reference HD 6970's clock rates of 880/5500 MHz, it still delivers almost the same performance as its faster cousin. What's important, the dual BIOS eliminates almost all the risk associated with BIOS reflashing.

 

If you’ve got a non-modifiable Radeon HD 6950, overclocking is yet another way to try to increase its performance. There is quite a lot of fine-tuning and monitoring utilities for such graphics cards, and the cards also have overheat protection, so the overclocking procedure is accessible even for inexperienced users. There is even a simpler way. You can buy a pre-overclocked graphics card from nearly any brand as they all offer such products now. Here are some examples:

As you can see, the cards from HIS and Sapphire have the highest clock rates among the six products. We’ve got a sample of the Sapphire card for our today's tests.

Closer Look at Sapphire Radeon HD 6950 2GB Toxic Edition

Package and Accessories

The graphics card is packed into a large box with a picture of a hooded and menacing person with blue eyes on the face side.

 

Information about the product can be found on the face and back sides of the box. Inside the colorful wrapper there is a cardboard box with an individual graphics card compartment. The card is sealed into a soft pack.

It’s nice that the manufacturer takes care that the product arrives to the user without a damaged cooler or broken PCB. The Sapphire Radeon HD 6950 Toxic Edition gets our praise for its robust packaging.

The accessories are praiseworthy, too. Besides the necessities, we found a few nice extras inside:

Here is a full list of the card’s accessories:

The Sapphire Radeon HD 6950 2GB Toxic Edition is priced at $299, which is about $30 more than the price of reference AMD Radeon HD 6950s.

PCB Design and Functionality

The card looks stylish and attractive. The black glossy casing of its cooler is decorated with a chrome-like plastic stripe and a picture of the same mysterious figure.

The round “lock” near the mounting bracket is just a plastic dummy, but it is sure to attract your friends’ curiosity. There is no metallic cover on the reverse side of the card. We noticed in our earlier reviews that it only worsened the cooling of Radeon HD 6950/5970 cards, so it's good that Sapphire has got rid of it.

The Radeon HD 6950 2GB Toxic Edition is equipped with a classic selection of five outputs: two DVIs, two mini-DisplayPorts, and one HDMI. There are as many as two vent grids in the card's mounting bracket for exhausting the hot air out of the system case:

The manufacturer obviously tried to increase cooling efficiency and lower the cooler's noise. Sapphire gets more points from us for such a meticulous attention to detail.

The card has power connectors, two CrossFireX connectors and a BIOS switch in their standard locations.

 

One of the distinguishing features of the Sapphire Radeon HD 6950 Toxic Edition is that it has one 6-pin and one 8-pin connector like a Radeon HD 6970, but not two 6-pin power connectors as the reference Radeon HD 6950. This must be due to its increased clock rates. Sapphire just wanted to make the card stable, especially if the user tries to overclock it further.

The PCB seems to be but slightly different from the reference one:

However, it is in the power circuit of the card that we discover its main feature. It is a digital voltage management module based on high-quality components:

The 8-phase power circuit is based on a CHiL Semiconductor CHL82289 controller. We couldn’t find any information about it.

The Cayman chip installed on our sample of the card was manufactured on the 5th week of 2011.

It has the standard Radeon HD 6950 configuration with 1408 unified shader processors, 88 texture-mapping units, and 32 raster operators. The GPU clock rate is increased on the Sapphire Radeon HD 6950 Toxic Edition and equals that of the reference Radeon HD 6970, i.e. 880 MHz (at a voltage of 1.176 volts). It is reduced to 250 MHz at a voltage of 0.9 volts in 2D mode.

The graphics card is equipped with 2 gigabytes of GDDR5 memory in FCFBGA chips from Hynix Semiconductor located on the face side of the PCB.

These H5GQ2H24MFR T2C chips have a default voltage of 1.5 volts and a rated frequency of 5000 MHz. Despite that, the Sapphire card has a memory frequency of 5200 MHz, which is 4% higher than that of the reference Radeon HD 6950. The memory clock rate is lowered to 600 MHz in 2D mode. The memory bus is 256 bits wide.

The GPU-Z utility has the following to report about the Toxic card from Sapphire:

Cooling System, Temperatures, Noise and Overclocking

The cooling system of the Sapphire Radeon HD 6950 Toxic Edition is a copy of the reference cooler, so we will just show you its photo here:

The card supports Sapphire’s TriXX utility that can report you exhaustive information about the graphics card and its drivers. It can also be used to adjust the voltage and frequency of the GPU and create multiple profiles with settings. You can set the speed range of the fan depending on temperature and do some other fine-tuning with it.

 

 

TriXX is quite sufficient for managing the card, yet we used our traditional toolset consisting of MSI Afterburner 2.2.0 Beta 5 and GPU-Z 0.5.4 to check out the card’s temperature.

We ran the Aliens vs. Predator (2010) test in five cycles with maximum graphics quality settings at 1920x1080 with 16x anisotropic filtering. We also fried the card up with the FurMark 1.9.1 stability test at 1920x1080. This test was carried out with a closed system case at an ambient temperature of 24°C.

Here are the results:


Aliens vs. Predator

FurMark 1.9.1

As you can see, the Sapphire card has the same temperature and fan speed as any regular Radeon HD 6950. However, the radial fan of the Radeon HD 6950 Toxic Edition seemed to be quieter than the cooler of the reference Radeon HD 6950/6970. We checked this out following our standard methods:

Indeed, the Sapphire card’s cooler is somewhat quieter and more comfortable than the reference cooler of Radeon HD 6950/6970 cards. On the other hand, neither of these cooling systems is really quiet even at the minimum speed of the fan, let alone in 3D applications.

Despite its pre-overclocked frequencies, the Sapphire card could be overclocked further to a GPU clock rate of 940 MHz and memory clock rate of 6000 MHz at the default voltages.

This result is rather typical of a Radeon HD 6970, so we can congratulate Sapphire on developing a very good product. By the way, the card didn’t get much hotter after we had overclocked it:

There was only one test on our list that the card failed to pass at the mentioned clock rates so we lowered them to 935/5960 MHz to ensure full stability.

As for unlocking the card and transforming it into an HD 6970, the manufacturer has already done all the modifications for the user. You only have to set the BIOS switch into the “1” position (with the card turned off, of course) and the graphics card becomes a full-featured Radeon HD 6970 with 1536 shader processors:

The card was perfectly stable in this mode whereas its temperature and overclocking potential were almost the same as before:

 

Testbed Configuration and Testing Methodology

All graphics cards were benchmarked in a closed system case with the following configuration:

In order to lower the dependence of the graphics cards performance on the overall platform speed, I overclocked our 32 nm six-core CPU with the multiplier set at 25x and “Load-Line Calibration” (Level 2) enabled to 4.5GHz. The processor Vcore was increased to 1.46875V in the mainboard BIOS:

The 6 GB of system DDR3 memory worked at 1.44 GHz frequency with 7-7-7-16_1T timings and 1.6V voltage. Turbo Boost and Hyper-Threading technologies were disabled during our test session.

The test session started on August 24, 2011. All tests were performed in Microsoft Windows 7 Ultimate x64 SP1 with all critical updates as of that date and the following drivers:

The graphics cards were tested only in one today’s most popular resolution: 1920x1080. The tests were performed in two image quality modes: “Quality+AF16x” – default texturing quality with enabled 16x anisotropic filtering and “Quality+ AF16x+AA4(8)x” with enabled 16x anisotropic filtering and full screen 4x anti-aliasing (MSAA) or 8x if the average framerate was high enough for comfortable gaming experience. We enabled anisotropic filtering and full-screen anti-aliasing from the game settings or configuration files. If the corresponding options were missing, we changed these settings in the Control Panels of Catalyst and GeForce/ION drivers. There were no other changes in the driver settings.

The list of games and applications used in this test includes two popular semi-synthetic benchmarking suites, one technical demo and 14 games of various genres:

If the game allowed recording the minimal fps readings, they were also added to the charts. We ran each game test or benchmark twice and took the best result for the diagrams, but only if the difference between them didn’t exceed 1%. If it did exceed 1%, we ran the tests at least one more time to achieve repeatability of results.

Performance

3DMark Vantage

3DMark 2011

Unigine Heaven Demo

BattleForge: Lost Souls

S.T.A.L.K.E.R.: Call of Pripyat

Left 4 Dead 2

Metro 2033: The Last Refuge

Just Cause 2

Aliens vs. Predator (2010)

Lost Planet 2

StarCraft 2: Wings of Liberty

Sid Meier’s Civilization V

Tom Clancy's H.A.W.X. 2

Crysis 2

Total War: Shogun 2

DiRT 3

World of Planes (alpha)

We don’t comment on each test since the results all fit into one general picture. The Sapphire Radeon HD 6950 Toxic Edition performs very well, leaving behind the theoretically faster and more expensive XFX Radeon HD 6970. When overclocked and in the HD 6970 mode, the Sapphire card gets even faster.

Here is a table with the full test results:

Conclusion

I have to say that we liked Sapphire Radeon HD 6950 Toxic Edition card very much. You can buy this card for $40-60 less than a regular Radeon HD 6970 and you get higher performance, digital voltage regulator circuitry and excellent overclocking potential. It is also a little quieter and comes with good accessories. If it had a unique and really quiet cooler, it would be just perfect.

By the way, there is a Radeon HD 6950 with an alternative cooler in Sapphire’s products range. It must be quieter than the reference coolers, so Sapphire only has to combine the best features of these two products to deliver the ideal Radeon HD 6950.

Nevertheless, Sapphire Radeon HD 6950 Toxic Edition is one of the best graphics cards in this class available today that is why we are proud to award it with our Editor's Choice title. It is, obviously, well deserved.