Compare any two graphics cards:
Radeon HD 5870 vs Radeon HD 7970
IntroThe Radeon HD 5870 makes use of a 40 nm design. AMD has set the core frequency at 850 MHz. The GDDR5 RAM is set to run at a frequency of 1200 MHz on this particular card. It features 1600(320x5) SPUs along with 80 Texture Address Units and 32 ROPs.
Compare all that to the Radeon HD 7970, which comes with a core clock speed of 925 MHz and a GDDR5 memory frequency of 1375 MHz. It also features a 384-bit bus, and uses a 28 nm design. It is made up of 2048 SPUs, 128 TAUs, and 32 Raster Operation Units.
(No game benchmarks for this combination yet.)
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
The Radeon HD 7970 should theoretically perform quite a bit faster than the Radeon HD 5870 overall. (explain)
Texel RateThe Radeon HD 7970 should be much (about 74%) more effective at AF than the Radeon HD 5870. (explain)
Pixel RateIf using a high screen resolution is important to you, then the Radeon HD 7970 is the winner, not by a very large margin though. (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 max amount of data (measured in MB per second) that can be transferred past the external memory interface in a second. The number is calculated by multiplying the card's interface width by its memory speed. In the case of DDR type RAM, it should be multiplied by 2 again. If it uses DDR5, multiply by 4 instead. The better the card's memory bandwidth, the faster the card will be in general. It especially helps with AA, High Dynamic Range and high resolutions.
Texel Rate: Texel rate is the maximum amount of texture map elements (texels) that are applied per second. This number is worked out by multiplying the total texture units of the card by the core clock speed of the chip. The better the texel rate, the better the video card will be at handling texture filtering (anisotropic filtering - AF). It is measured in millions of texels per second.
Pixel Rate: Pixel rate is the most pixels the graphics card can possibly write to the local memory in a second - measured in millions of pixels per second. Pixel rate is calculated by multiplying the amount of Raster Operations Pipelines by the the core clock speed. ROPs (Raster Operations Pipelines - sometimes also referred to as Render Output Units) are responsible for outputting the pixels (image) to the screen. The actual pixel fill rate also depends on many other factors, especially the memory bandwidth of the card - the lower the bandwidth is, the lower the ability to get to the max fill rate.