Compare any two graphics cards:
Radeon HD 5870 vs Radeon HD 7970
IntroThe Radeon HD 5870 features core speeds of 850 MHz on the GPU, and 1200 MHz on the 1024 MB of GDDR5 RAM. It features 1600(320x5) SPUs along with 80 TAUs and 32 Rasterization Operator Units.
Compare all of that to the Radeon HD 7970, which comes with a clock speed of 925 MHz and a GDDR5 memory speed of 1375 MHz. It also uses a 384-bit memory bus, and makes use of a 28 nm design. It features 2048 SPUs, 128 Texture Address Units, and 32 Raster Operation Units.
(No game benchmarks for this combination yet.)
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
In theory, the Radeon HD 7970 should be a lot faster than the Radeon HD 5870 in general. (explain)
Texel RateThe Radeon HD 7970 is a lot (about 74%) more effective at AF than the Radeon HD 5870. (explain)
Pixel RateThe Radeon HD 7970 will be just a bit (more or less 9%) faster with regards to AA than the Radeon HD 5870, and will be capable of handling higher screen resolutions while still performing well. (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: Bandwidth is the max amount of information (counted in megabytes per second) that can be moved past the external memory interface within a second. It is calculated by multiplying the interface width by its memory clock speed. If the card has DDR memory, the result should be multiplied by 2 once again. If it uses DDR5, multiply by ANOTHER 2x. The better the memory bandwidth, the faster the card will be in general. It especially helps with anti-aliasing, HDR and high resolutions.
Texel Rate: Texel rate is the maximum number of texture map elements (texels) that are applied in one second. This is calculated by multiplying the total texture units of the card by the core speed of the chip. The higher this number, the better the graphics card will be at handling 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 chip can possibly write to its local memory per second - measured in millions of pixels per second. Pixel rate is calculated by multiplying the amount of Raster Operations Pipelines by the clock speed of the card. ROPs (Raster Operations Pipelines - sometimes also referred to as Render Output Units) are responsible for filling the screen with pixels (the image). The actual pixel rate also depends on many other factors, especially the memory bandwidth - the lower the memory bandwidth is, the lower the ability to reach the maximum fill rate.