Compare any two graphics cards:
Radeon HD 6970 vs Radeon HD 7870
IntroThe Radeon HD 6970 has core clock speeds of 880 MHz on the GPU, and 1375 MHz on the 2048 MB of GDDR5 RAM. It features 1536 SPUs along with 96 Texture Address Units and 32 ROPs.
Compare that to the Radeon HD 7870, which uses a 28 nm design. AMD has clocked the core speed at 1000 MHz. The GDDR5 memory is set to run at a speed of 1200 MHz on this model. It features 1280 SPUs as well as 80 Texture Address Units and 32 ROPs.
(No game benchmarks for this combination yet.)
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
Performance-wise, the Radeon HD 6970 should in theory be a little bit superior to the Radeon HD 7870 overall. (explain)
Texel RateThe Radeon HD 6970 should be a bit (about 6%) faster with regards to anisotropic filtering than the Radeon HD 7870. (explain)
Pixel RateIf using high levels of AA is important to you, then the Radeon HD 7870 is superior to the Radeon HD 6970, but only just. (explain)
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.
Please note that the price comparisons are based on search keywords - sometimes it might show cards with very similar names that are not exactly the same as the one chosen in the comparison. We do try to filter out the wrong results as best we can, though.
Memory Bandwidth: Memory bandwidth is the maximum amount of data (in units of MB per second) that can be moved over the external memory interface in a second. It's worked out by multiplying the bus width by its memory clock speed. If the card has DDR memory, it must be multiplied by 2 once again. If it uses DDR5, multiply by 4 instead. The higher the memory bandwidth, the better the card will be in general. It especially helps with AA, HDR and high resolutions.
Texel Rate: Texel rate is the maximum number of texture map elements (texels) that are processed in one second. This is worked out by multiplying the total texture units of the card by the core clock speed of the chip. The better this number, the better the card will be at texture filtering (anisotropic filtering - AF). It is measured in millions of texels processed 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. The number is calculated by multiplying the number of Render Output Units by the the core clock speed. ROPs (Raster Operations Pipelines - also called Render Output Units) are responsible for drawing the pixels (image) on the screen. The actual pixel rate is also dependant on quite a few other factors, especially the memory bandwidth - the lower the memory bandwidth is, the lower the potential to reach the max fill rate.