Compare any two graphics cards:
GeForce GTX 660 Ti vs Radeon HD 7950
IntroThe GeForce GTX 660 Ti features a core clock speed of 915 MHz and a GDDR5 memory speed of 1500 MHz. It also uses a 192-bit bus, and makes use of a 28 nm design. It is made up of 1344 SPUs, 112 Texture Address Units, and 24 ROPs.
Compare those specifications to the Radeon HD 7950, which comes with a clock speed of 800 MHz and a GDDR5 memory frequency of 1250 MHz. It also uses a 384-bit memory bus, and uses a 28 nm design. It is comprised of 1792 SPUs, 112 TAUs, and 32 Raster Operation Units.
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
Theoretically speaking, the Radeon HD 7950 will be 67% quicker than the GeForce GTX 660 Ti overall, because of its greater bandwidth. (explain)
Texel RateThe GeForce GTX 660 Ti will be a little bit (approximately 14%) better at texture filtering than the Radeon HD 7950. (explain)
Pixel RateIf running with high levels of AA is important to you, then the Radeon HD 7950 is the winner, but only just. (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 maximum amount of data (counted in megabytes per second) that can be moved over the external memory interface within a second. The number is calculated by multiplying the bus width by the speed of its memory. If the card has DDR memory, the result should be multiplied by 2 once again. If it uses DDR5, multiply by ANOTHER 2x. The higher the bandwidth is, 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 texture map elements (texels) that are applied per second. This is calculated by multiplying the total texture units by the core clock speed of the chip. The higher the texel rate, the better the card will be at handling texture filtering (anisotropic filtering - AF). It is measured in millions of texels applied in a second.
Pixel Rate: Pixel rate is the maximum amount of pixels the video card can possibly write to its local memory in one second - measured in millions of pixels per second. The number is calculated by multiplying the number of colour ROPs by the the core clock speed. ROPs (Raster Operations Pipelines - also sometimes called Render Output Units) are responsible for filling the screen with pixels (the image). The actual pixel output rate also depends on lots of other factors, especially the memory bandwidth of the card - the lower the memory bandwidth is, the lower the ability to reach the max fill rate.