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Radeon HD 6870 vs Radeon HD 6990
Intro
The Radeon HD 6870 makes use of a 40 nm design. ATi has clocked the core speed at 900 MHz. The GDDR5 RAM runs at a frequency of 1050 MHz on this specific model. It features 1120 SPUs as well as 56 TAUs and 32 ROPs.Compare those specifications to the Radeon HD 6990, which features GPU core speed of 830 MHz, and 2048 MB of GDDR5 RAM running at 1250 MHz through a 256-bit bus. It also is made up of 1536 SPUs, 96 Texture Address Units, and 32 Raster Operation Units.
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
| Radeon HD 6870 |
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151 Watts |
| Radeon HD 6990 |
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375 Watts |
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Memory Bandwidth
As far as performance goes, the Radeon HD 6990 should in theory be quite a bit superior to the Radeon HD 6870 overall. (explain)
| Radeon HD 6990 |
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320000 MB/sec |
| Radeon HD 6870 |
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134400 MB/sec |
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Texel Rate
The Radeon HD 6990 is quite a bit (approximately 216%) faster with regards to texture filtering than the Radeon HD 6870. (explain)| Radeon HD 6990 |
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159360 Mtexels/sec |
| Radeon HD 6870 |
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50400 Mtexels/sec |
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Pixel Rate
The Radeon HD 6990 should be a lot (about 84%) more effective at anti-aliasing than the Radeon HD 6870, and able to handle higher screen resolutions better. (explain)| Radeon HD 6990 |
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53120 Mpixels/sec |
| Radeon HD 6870 |
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28800 Mpixels/sec |
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Please note that the above 'benchmarks' are all just theoretical - the results were calculated based on the card's specifications, and real-world performance may (and probably will) vary at least a bit.
One or more cards in this comparison are multi-core. This means that their bandwidth, texel and pixel rates are theoretically doubled - this does not mean the card will actually perform twice as fast, but only that it should in theory be able to. Actual game benchmarks will give a more accurate idea of what it's capable of.
Price Comparison
Please note that the price comparisons are based on search keywords, and might not be the exact same card listed on this page. We have no control over the accuracy of their search results.
Radeon HD 6870Amazon.com
Other US-based stores
Amazon.co.uk
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Amazon.fr
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Radeon HD 6990Amazon.com
Other US-based stores
Amazon.co.uk
Amazon.de
Amazon.fr
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Specifications
| Model | Radeon HD 6870 | Radeon HD 6990 |
|---|---|---|
| Manufacturer | ATi | ATi |
| Year | October 2010 | March 2011 |
| Code Name | Barts XT | Antilles |
| Fab Process | 40 nm | 40 nm |
| Bus | PCIe x16 | PCIe 2.1 x16 |
| Memory | 1024 MB | 2048 MB (x2) |
| Core Speed | 900 MHz | 830 MHz (x2) |
| Shader Speed | N/A MHz | (N/A) MHz (x2) |
| Memory Speed | 1050 MHz | 1250 MHz (x2) |
| Unified Shaders | 1120 | 1536 (x2) |
| Texture Mapping Units | 56 | 96 (x2) |
| Render Output Units | 32 | 32 (x2) |
| Bus Type | GDDR5 | GDDR5 |
| Bus Width | 256-bit | 256-bit (x2) |
| DirectX Version | DirectX 11 | DirectX 11 |
| OpenGL Version | OpenGL 4.1 | OpenGL 4.1 |
| Power (Max TDP) | 151 watts | 375 watts |
| Shader Model | 5.0 | 5.0 |
| Bandwidth | 134400 MB/sec | 320000 MB/sec |
| Texel Rate | 50400 Mtexels/sec | 159360 Mtexels/sec |
| Pixel Rate | 28800 Mpixels/sec | 53120 Mpixels/sec |
Memory Bandwidth: Memory bandwidth is the maximum amount of information (counted in megabytes per second) that can be transferred over the external memory interface in one second. It's calculated by multiplying the bus width by its memory clock speed. If the card has DDR type memory, it should be multiplied by 2 again. If it uses DDR5, multiply by ANOTHER 2x. The higher the card's memory bandwidth, the better the card will be in general. It especially helps with anti-aliasing, High Dynamic Range and high resolutions.
Texel Rate: Texel rate is the maximum texture map elements (texels) that are applied per second. This number is calculated by multiplying the total number of texture units by the core clock speed of the chip. The better this number, the better the graphics card will be at texture filtering (anisotropic filtering - AF). It is measured in millions of texels applied in one second.
Pixel Rate: Pixel rate is the most pixels that the graphics card can possibly write to the local memory per second - measured in millions of pixels per second. Pixel rate is calculated by multiplying the amount of Render Output Units by the the core speed of the card. ROPs (Raster Operations Pipelines - also sometimes called Render Output Units) are responsible for drawing the pixels (image) on the screen. The actual pixel output rate is also dependant on many other factors, most notably the memory bandwidth of the card - the lower the memory bandwidth is, the lower the potential to reach the max fill rate.
Comments
One Response to “Radeon HD 6870 vs Radeon HD 6990”It would make sense to compare
the 2 model cards with the same amount of VRAM