Compare any two graphics cards:
Radeon HD 6790 vs Radeon HD 7950
IntroThe Radeon HD 6790 has a clock frequency of 840 MHz and a GDDR5 memory frequency of 1050 MHz. It also makes use of a 256-bit bus, and uses a 40 nm design. It is comprised of 800 SPUs, 40 TAUs, and 16 ROPs.
Compare that to the Radeon HD 7950, which comes with a clock speed of 800 MHz and a GDDR5 memory frequency of 1250 MHz. It also features a 384-bit bus, and uses a 28 nm design. It is comprised 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, due to its greater bandwidth. (explain)
Texel RateThe Radeon HD 7950 is much (about 167%) faster with regards to anisotropic filtering than the Radeon HD 6790. (explain)
Pixel RateThe Radeon HD 7950 will be a lot (approximately 90%) more effective at full screen anti-aliasing than the Radeon HD 6790, and will be capable of handling higher 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 largest amount of data (measured in megabytes per second) that can be transported over the external memory interface within a second. The number is worked out by multiplying the bus width by the speed of its memory. In the case of DDR memory, the result should be multiplied by 2 again. If DDR5, multiply by ANOTHER 2x. The higher the bandwidth is, the better the card will be in general. It especially helps with AA, High Dynamic Range and high resolutions.
Texel Rate: Texel rate is the maximum number of texture map elements (texels) that are processed per second. This is worked out by multiplying the total number of texture units of the card by the core clock speed of the chip. The better this number, the better the graphics card will be at handling 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 could possibly record to the local memory in a second - measured in millions of pixels per second. Pixel rate is worked out by multiplying the amount of Raster Operations Pipelines 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 rate also depends on lots of other factors, especially the memory bandwidth - the lower the memory bandwidth is, the lower the ability to get to the max fill rate.