Compare any two graphics cards:
Geforce GTX 680 vs Radeon HD 7970
IntroThe Geforce GTX 680 features a clock speed of 1006 MHz and a GDDR5 memory speed of 1502 MHz. It also makes use of a 256-bit memory bus, and uses a 28 nm design. It is made up of 1536 SPUs, 128 Texture Address Units, and 32 Raster Operation Units.
Compare all of that to the Radeon HD 7970, which comes with a clock speed of 925 MHz and a GDDR5 memory frequency of 1375 MHz. It also features a 384-bit bus, and makes use of a 28 nm design. It is comprised 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)
Theoretically speaking, the Radeon HD 7970 will be 37% quicker than the Geforce GTX 680 in general, due to its greater data rate. (explain)
Texel RateThe Geforce GTX 680 will be a bit (more or less 9%) more effective at AF than the Radeon HD 7970. (explain)
Pixel RateThe Geforce GTX 680 is a little bit (approximately 9%) better at full screen anti-aliasing than the Radeon HD 7970, and also will be able to handle higher resolutions more effectively. (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 data (counted in megabytes per second) that can be moved across the external memory interface within a second. It is calculated by multiplying the card's bus width by its memory speed. If the card has DDR memory, it should be multiplied by 2 once again. If it uses DDR5, multiply by ANOTHER 2x. The higher the card's memory bandwidth, the better the card will be in general. It especially helps with anti-aliasing, High Dynamic Range and high resolutions.
Texel Rate: Texel rate is the maximum amount of texture map elements (texels) that are processed per second. This number is worked out by multiplying the total texture units by the core clock speed of the chip. The better this number, the better the card will be at texture filtering (anisotropic filtering - AF). It is measured in millions of texels in one second.
Pixel Rate: Pixel rate is the maximum amount of pixels the video card could possibly write to its local memory in one second - measured in millions of pixels per second. The figure is calculated by multiplying the number of colour ROPs by the clock speed of the card. ROPs (Raster Operations Pipelines - aka 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, especially the memory bandwidth - the lower the memory bandwidth is, the lower the potential to reach the max fill rate.