Compare any two graphics cards:
Radeon HD 5850 vs Radeon HD 7970
IntroThe Radeon HD 5850 comes with clock speeds of 725 MHz on the GPU, and 1000 MHz on the 1024 MB of GDDR5 RAM. It features 1440(288x5) SPUs along with 72 Texture Address Units and 32 ROPs.
Compare all that to the Radeon HD 7970, which comes with GPU core speed of 925 MHz, and 3072 MB of GDDR5 RAM set to run at 1375 MHz through a 384-bit bus. It also is made up of 2048 SPUs, 128 Texture Address Units, and 32 Raster Operation Units.
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
In theory, the Radeon HD 7970 should be quite a bit faster than the Radeon HD 5850 in general. (explain)
Texel RateThe Radeon HD 7970 is a lot (approximately 127%) better at texture filtering than the Radeon HD 5850. (explain)
Pixel RateThe Radeon HD 7970 will be a lot (about 28%) better at full screen anti-aliasing than the Radeon HD 5850, and should be capable of handling higher screen resolutions without slowing down too much. (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 across the external memory interface within a second. It is worked out by multiplying the card's bus width by its memory clock speed. If it uses DDR memory, it must be multiplied by 2 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 amount of texture map elements (texels) that can be processed per second. This number is worked out by multiplying the total texture units by the core speed of the chip. The higher this number, the better the card will be at texture filtering (anisotropic filtering - AF). It is measured in millions of texels in a second.
Pixel Rate: Pixel rate is the most pixels the video card can possibly write to its local memory per second - measured in millions of pixels per second. The figure is worked out by multiplying the number of Render Output Units by the the core 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 fill rate is also dependant on quite a few other factors, most notably the memory bandwidth - the lower the memory bandwidth is, the lower the ability to reach the max fill rate.