AMD Radeon HD 6950 and 6970 Video Card Review

[nextpage title=”Introduction”]

AMD released yesterday their latest high-end video card series, the Radeon HD 6900. Let’s take a look at the two models that were released, the Radeon HD 6950 and the Radeon HD 6970.

The video cards we are reviewing are the reference models from AMD. When a video card is first launched, all “manufacturers” buy their video cards already assembled from AMD and only add their sticker to it. One or other manufacturer may add an overclocking, but physically all cards are absolutely identical. Only after a while manufacturers start launching customized solutions, changing the cooler and, sometimes, redesigning the printed circuit board. Therefore, you should expect the same performance level on video cards based on the same graphics chip from different vendors, as long as they run at the same clock rates and have the same amount of video memory, of course.

The Radeon HD 6950 comes with a suggested price of USD 300, the same price as the Radeon HD 5870, which will be retired. The main competitor for the Radeon HD 6950 is the GeForce GTX 470, a product that is being phased out (unfortunately we didn’t have one available). So, in our review we will compare it mainly with the Radeon HD 5870, since they cost the same, and with the Radeon HD 6870, which is about USD 60 cheaper, so we will be able to tell what performance level extra USD 60 can buy.

The Radeon HD 6970 comes with a suggested price of USD 370, competing directly with the new GeForce GTX 570.

These two new video cards come with 2 GB memory, and AMD partners will probably offer models with less memory at lower price points in the future.

In the table below we compare the main specs of the video cards included in our review. They are all DirectX 11 parts.

Video Card	Core Clock	Shader Clock	Memory Clock (Real)	Memory Clock (Effective)	Memory Interface	Memory Transfer Rate	Memory	Shaders	Price
GeForce GTX 570	732 MHz	1,464 MHz	1.9 GHz	3.8 GHz	320-bit	152 GB/s	1.28 GB GDDR5	480	USD 350
Radeon HD 5870	850 MHz	850 MHz	2.4 GHz	4.8 GHz	256-bit	153.6 GB/s	1 GB GDDR5	1,600	USD 290
Radeon HD 6870	900 MHz	900 MHz	2.1 GHz	4.2 GHz	256-bit	134.4 GB/s	1 GB GDDR5	1,120	USD 240
Radeon HD 6950	800 MHz	800 MHz	2.5 GHz	5 GHz	256-bit	160 GB/s	2 GB GDDR5	1,408	USD 300
Radeon HD 6970	880 MHz	880 MHz	2.75 GHz	5.5 GHz	256-bit	176 GB/s	2 GB GDDR5	1,536	USD 370

Prices were researched at Newegg.com on the day we published this review.

You can compare the specs of these video cards with other video cards by taking a look at our AMD ATI Chips Comparison Table and NVIDIA Chips Comparison Table tutorials.

Now let’s take an in-depth look at the two new models released by AMD. Let’s start with the Radeon HD 6950.

[nextpage title=”The AMD Radeon HD 6950″]

Below we have an overall look at the AMD Radeon HD 6950 reference model. It requires two six-pin auxiliary power connectors.

Figure 1: AMD Radeon HD 6950

 Figure 2: AMD Radeon HD 6950

This video card has two mini DisplayPort 1.2, one HDMI 1.4a connector, and two DVI-D connectors. The new DisplayPort 1.2 standard has a technique called multi-stream transport, which allows several video monitors to be installed using only one connector of the video card. Each mini DisplayPort 1.2 supports up to three video monitors (installed by either daisy-chaining the monitors or using a multi-stream transport hub), making this video card to be able to be connected up to six monitors using only two connectors.

Figure 3: Video connectors

A new feature AMD is introducing with the Radeon HD 6900 series is the presence of two ROM chips, one of them being write-protected. So if you make a mistake while flashing the video card BIOS (a feature used by advanced users when they want to set a “permanent” overclocking), you will be able to switch back to the default (protected) BIOS by simply changing the position of a small switch (located near the CrossFireX connector), allowing you to fix the problem. Without this feature, a bad BIOS upgrade “kills” the video card.

Figure 4: BIOS selection switch

[nextpage title=”The AMD Radeon HD 6950 (Cont’d)”]

In Figure 5, you can see the video card with its cooler removed and, in Figure 6, a close-up of the voltage regulator circuit. AMD did a great job here, using a high-end configuration, with six phases for the GPU and two phases for the memory chips. The voltage regulator is controlled by a Volterra VT1556MF chip, while each phase is driven by a Volterra VT1636SF chip, which integrated the functions of the traditional three MOSFET transistors that are required (translation: higher efficiency). Unfortunately Volterra doesn’t post datasheets. The voltage regulator also uses ferrite-core coils (which make the regulator to have higher efficiency because they have lower energy loss than iron-core coils) and solid capacitors.

Figure 5: Video card with the cooler removed

Figure 6: Voltage regulator circuit

Figure 7: Back of the video card

The GPU cooler can be seen in
Figure 8. It has a copper base using vapor chamber technology, which is the same technology behind heat-pipes, aluminum fins, and a 70 mm radial fan.

Figure 8: The GPU cooler

The Radeon HD 6850 uses eight 2 Gbit GDDR5 chips, making its 2 GB video memory (2 Gbit x 8 = 2 GB). Each chip is connected to the GPU using a 32-bit data lane, making the video card’s 256-bit memory interface (32 bits x 8 = 256).

The chips used are H5GQ2H24MFR-T2C parts from Hynix, which support up to 2.5 GHz (5 GHz DDR) and since on this video card memory is accessed at 2.5 GHz (5 GHz DDR), there is no margin for you to increase the memory clock rate while keeping the chips inside the maximum they support. Of course you can always try to overclock the memory chips above their specs.

Figure 9: Memory chips

Now let’s take a look at the Radeon HD 6970.

[nextpage title=”The AMD Radeon HD 6970″]

Below we have an overall look at the AMD Radeon HD 6970 reference model. It requires one six-pin and one eight-pin auxiliary power connector.

Figure 10: AMD Radeon HD 6970

Figure 11: AMD Radeon HD 6970

Like the Radeon HD 6950, the Radeon HD 6970 has two mini DisplayPort 1.2, one HDMI 1.4a connector, and two DVI-D connectors. The new DisplayPort 1.2 standard has a technique called multi-stream transport, which allows several video monitors to be installed using only one connector of the video card. Each mini DisplayPort 1.2 supports up to three video monitors (installed by either daisy-chaining the monitors or using a multi-stream transport hub), making this video card to be able to be connected up to six monitors using only two connectors.

Figure 12: Video connectors

The Radeon HD 6970 also has two BIOS chips, feature that we’ve already discussed (see Figure 4).

[nextpage title=”The AMD Radeon HD 6970 (Cont’d)”]

In Figure 13, you can see the video card with its cooler removed and, in Figure 14, a close-up of the voltage regulator circuit, which is identical to the one used on the Radeon HD 6850.

Figure 13: Video card with the cooler removed

Figure 14: Voltage regulator circuit

Figure 15: Back of the video card

The GPU cooler used on the Radeon HD 6970 is identical to the one used on the Radeon HD 6950 and was already discussed.

The Radeon HD 6970 uses eight 2 Gbit GDDR5 chips, making its 2 GB video memory (2 Gbit x 8 = 2 GB). Each chip is connected to the GPU using a 32-bit data lane, making the video card’s 256-bit memory interface (32 bits x 8 = 256).

The chips used are H5GQ2H24MFR-R0C parts from Hynix, which support up to 3 GHz (6 GHz DDR) and since on this video card memory is accessed at 2.75 GHz (5.5 GHz DDR), there is a 500 MHz (9%) margin for you to increase the memory clock rate while keeping the chips inside the maximum they support. Of course you can always try to overclock the memory chips above their specs.

Figure 16: Memory chips

Now let’s check the results achieved by the Radeon HD 6950 and Radeon HD 6970.[nextpage title=”How We Tested”]

During our benchmarking sessions, we used the configuration listed below. Between our benchmarking sessions the only variable was the video card being tested.

Hardware Configuration

• CPU: Core i7 Extreme 965 (3.2 GHz, 8 MB L2 memory cache)
• Motherboard: MSI Big Bang XPower (1.3 BIOS)
• Memories: 3x 2 GB G.Skill F3-10666CL7T-6GBPK (DDR3-1333/PC3-10666, CL7-7-7-18)
• Hard disk drive: Western Digital VelociRaptor WD3000GLFS (300 GB, SATA-300, 10,000 rpm, 16 MB cache)
• Video monitor: Samsung SyncMaster 305T (30” LCD, 2560×1600)
• Power Supply: SilverStone Element ST75EF
• CPU Cooler: Intel stock
• Optical Drive: LG GSA-H54N

Software Configuration

• Windows 7 Ultimate 64-bit
• Video resolution: 2560×1600 @ 60 Hz

Driver Versions

• AMD/ATI video driver version: Catalyst 10.12 beta
• NVIDIA video driver version: 263.09
• Intel Inf driver version: 9.1.2.1008

Software Used

• 3DMark 11 Professional 1.0.0
• Aliens vs. Predator + Benchmark Tool
• Call of Duty 4 – Patch 1.7
• Crysis Warhead – Patch 1.1 + HOC Bench Crysis Warhead Benchmark Tool 1.1.1
• Far Cry 2 – Patch 1.03
• Lost Planet 2

Error Margin

We adopted a 3% error margin. Thus, differences below 3% cannot be considered relevant. In other words, products with a performance difference below 3% should be considered as having similar performance.

[nextpage title=”Call of Duty 4″]

Call of Duty 4 is a DirectX 9 game implementing high-dynamic range (HDR) and its own physics engine, which is used to calculate how objects interact. For example, if you shoot, exactly what will happen to the object when the bullet hits it? Will it break? Will it move? Will the bullet bounce back? It gives a more realistic experience to the user.

To get accurate results, we had to disable the 80 FPS limit in the game. To do this, input the command, “/seta com_maxfps 1000” (minus the quotes) into the console (` key). It can be set to any number greater than 200.

We ran this program at three 16:10 widescreen resolutions, 1680×1050, 1920×1200, and 2560×1600, maxing out all image quality controls (i.e., everything was set to the maximum values in the Graphics and Texture menus). We used the internal game benchmarking feature, running a demo provided by NVIDIA called “wetwork.”We are putting this demo here for downloading if you want to run your own benchmarks. We ran the demo five times, and the results below are the average number of frames per second (FPS) achieved by each video card.

Call of Duty 4 – Maximum	1680×1050
Radeon HD 6970	177.4
GeForce GTX 570	169.0
Radeon HD 6950	155.6
Radeon HD 5870	150.3
Radeon HD 6870	142.4

Call of Duty 4 – Maximum	1920×1200
Radeon HD 6970	162.3
GeForce GTX 570	144.6
Radeon HD 5870	130.8
Radeon HD 6950	130.4
Radeon HD 6870	123.5

Call of Duty 4 – Maximum	2560×1600
Radeon HD 6970	108.4
GeForce GTX 570	100.4
Radeon HD 6950	92.2
Radeon HD 5870	91.8
Radeon HD 6870	87.3

[nextpage title=”Crysis Warhead”]

Crysis Warhead is a DirectX 10 game based on the same engine as the original Crysis, but optimized (it runs under DirectX 9.0c when installed on Windows XP).

We used the HardwareOC Crysis Warhead Benchmark Tool to collect the data for this test.We ran this program at three 16:10 widescreen resolutions, 1680×1050, 1920×1200, and 2560×1600, all at very high image quality (but with no anti-aliasing and no anisotropic filtering) and using the Airfield demo. The results below are the number of frames per second achieved by each video card.

Crysis Warhead – Very High	1680×1050
GeForce GTX 570	44
Radeon HD 6970	39
Radeon HD 6950	36
Radeon HD 5870	34
Radeon HD 6870	32

Crysis Warhead – Very High	1920×1200
GeForce GTX 570	38
Radeon HD 6970	34
Radeon HD 6950	31
Radeon HD 5870	30
Radeon HD 6870	27

Crysis Warhead – Very High	2560×1600
Radeon HD 6970	24
GeForce GTX 570	24
Radeon HD 6950	21
Radeon HD 5870	21
Radeon HD 6870	18

[nextpage title=”Far Cry 2″]

Far Cry 2 is based on an entirely new game engine called Dunia, which is DirectX 10 when played under Windows Vista with a DirectX 10 compatible video card.

We used the benchmarking utility that comes with this game, setting image quality to Ultra High (with x8 anti-aliasing) and running the “Ranch Long” demo three times. The results below are expressed in frames per second and are an arithmetic average of the three results collected.

[nextpage title=”Aliens vs. Predator”]

Aliens vs. Predator is a DirectX 11 game that makes full use of tessellation and advanced shadow rendering. We used the Aliens vs. Predator Benchmark Tool developed by Rebellion. This program reads its configuration from a text file (our configuration files can be found here). We ran this program at 1680×1050, 1920×1200, and 2560×1600 resolutions, with very high settings, 16x anisotropic filtering and 4x anti-aliasing.

[nextpage title=”Lost Planet 2″]

Lost Planet 2 is a game that uses a lot of DirectX 11 features, like tessellation (to round out the edges of polygonal models), displacement maps (added to the tessellated mesh to add fine grain details), DirectCompute soft body simulation (to introduce more realism in the “boss” monsters), and DirectCompute wave simulation (to introduce more realism in the physics calculations in water surfaces; when you move or when gunshots and explosions hit the water, it moves accordingly). We reviewed the video cards using Lost Planet 2 internal benchmarking features, choosing the “Benchmark A” (we know that “Benchmark B” is the one recommended for reviewing video cards, however, at least with us, results were inconsistent). We set graphics at “high,” anti-aliasing at “4x” and DX11 at “full.” The results below are the number of frames per second generated by each video card.

[nextpage title=”3DMark 11 Professional”]

3DMark 11 Professional measures Shader 5.0 (i.e., DirectX 11) performance. We ran this program at three 16:10 widescreen resolutions, 1680×1050, 1920×1200, and 2560×1600, selecting the four graphics tests available and deselecting the other tests available. We used two image quality settings for each resolution, “Performance” and “Extreme,” both at their default settings. The results being compared are the “GPU Score” achieved by each video card.

[nextpage title=”Conclusions”]

The new Radeon HD 6970 is a very good contender to the GeForce GTX 570. We ran six games and simulations for a total of 21 tests, and the Radeon HD 6970 was faster than the GeForce GTX 570 in three of them: Call of Duty 4 (between 5% and 12% faster), Aliens vs. Predator (between 11% and 13%) , and 3DMark11 (between 4% and 17% faster). The GeForce GTX 570 was faster on the other three: Crysis Warhead (up to 13% faster), FarCry 2 (up to 21% faster) and Lost Planet 2 (between 7% and 36% faster). Therefore, which video card is the fastest will depend on the game and video configuration you decide to run.

Costing USD 370, the Radeon HD 6970 is 23% more expensive than the Radeon HD 6950. During our tests, however, the performance difference between the two touched 23% only a very few times: the Radeon HD 6970 was between 14% and 24% faster on Call of Duty 4, between 8% and 14% faster on Crysis Warhead, between 4% and 10% faster on FarCry 2, between 13% and 14% faster on Aliens vs. Predator, between 12% and 38% faster on Lost Planet 2, and between 13% and 17% faster on 3DMark 11 than the Radeon HD 6950. This may indicate that the Radeon HD 6950 brings a better bang for the buck. Let’s see.

The Radeon HD 6950 was only marginally faster than the Radeon HD 5870 in most games and simulations we ran, with two important exceptions: Aliens vs. Predator (between 12% and 14% faster) and Lost Planet 2 (between 10% and 15% faster). Since the Radeon HD 6950 comes with a price that is actually lower than the one Radeon HD 5870 used to carry a couple of months ago, this is indeed good news if you have USD 300 to spend on a video card.

Against the Radeon HD 6870, the Radeon HD 6950 was between 6% and 9% faster on Call of Duty 4, between 13% and 17% faster on Crysis Warhead, between 11% and 19% faster on FarCry 2, between 34% and 37% faster on Aliens vs. Predator, between 15% and 29% faster on Lost Planet 2, and between 7% and 10% faster on 3DMark 11. As you can see, the biggest differences were seen on the DirectX 11 games we included. The extra USD 60 can bring you a lot more performance in these games (spending 25% more will give you more than 25% performance improvement), if you have the money, of course.

Summarizing our conclusions: the Radeon HD 6970 has the GeForce GTX 570 as a strong competitor, and which one is the fastest will depend on the game and video configuration you use. The Radeon HD 6950 presents a better bang for the buck, being a nice replacement for the Radeon HD 5870, with similar performance in most games, but with improved performance on DirectX 11 games.