Compare any two graphics cards:
Radeon HD 6790 vs Radeon HD 7950
IntroThe Radeon HD 6790 comes with a GPU core speed of 840 MHz, and the 1024 MB of GDDR5 memory is set to run at 1050 MHz through a 256-bit bus. It also features 800 SPUs, 40 Texture Address Units, and 16 ROPs.
Compare those specifications to the Radeon HD 7950, which has a clock frequency of 800 MHz and a GDDR5 memory speed of 1250 MHz. It also makes use of a 384-bit memory bus, and makes use of a 28 nm design. It is made up of 1792 SPUs, 112 Texture Address Units, and 32 ROPs.
(No game benchmarks for this combination yet.)
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
Theoretically speaking, the Radeon HD 7950 will be 79% quicker than the Radeon HD 6790 overall, because of its greater bandwidth. (explain)
Texel RateThe Radeon HD 7950 is a lot (about 167%) more effective at texture filtering than the Radeon HD 6790. (explain)
Pixel RateThe Radeon HD 7950 will be a lot (approximately 90%) better at anti-aliasing than the Radeon HD 6790, 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 information (measured in megabytes per second) that can be transported across the external memory interface within a second. It is calculated by multiplying the card's interface width by its memory clock speed. If the card has DDR RAM, the result should be multiplied by 2 once again. If DDR5, multiply by ANOTHER 2x. The better the card's memory bandwidth, the faster the card will be in general. It especially helps with anti-aliasing, HDR and higher screen resolutions.
Texel Rate: Texel rate is the maximum texture map elements (texels) that can be processed per second. This figure is calculated by multiplying the total texture units of the card by the core clock speed of the chip. The higher this number, the better the video card will be at texture filtering (anisotropic filtering - AF). It is measured in millions of texels processed per second.
Pixel Rate: Pixel rate is the maximum number of pixels that the graphics chip could possibly write to the local memory per second - measured in millions of pixels per second. The figure is calculated by multiplying the number of Raster Operations Pipelines by the the core clock speed. ROPs (Raster Operations Pipelines - aka Render Output Units) are responsible for drawing the pixels (image) on the screen. The actual pixel rate is also dependant on lots of other factors, most notably the memory bandwidth - the lower the memory bandwidth is, the lower the ability to reach the maximum fill rate.