Compare any two graphics cards:
GeForce GTX 460 1GB vs Radeon HD 6870
IntroThe GeForce GTX 460 1GB comes with a core clock speed of 675 MHz and a GDDR5 memory speed of 900 MHz. It also features a 256-bit bus, and uses a 40 nm design. It features 336 SPUs, 56 Texture Address Units, and 32 ROPs.
Compare those specifications to the Radeon HD 6870, which comes with a core clock speed of 900 MHz and a GDDR5 memory frequency of 1050 MHz. It also makes use of a 256-bit memory bus, and uses a 40 nm design. It is comprised of 1120 SPUs, 56 TAUs, and 32 ROPs.
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
As far as performance goes, the Radeon HD 6870 should in theory be just a bit better than the GeForce GTX 460 1GB overall. (explain)
Texel RateThe Radeon HD 6870 is quite a bit (approximately 33%) more effective at texture filtering than the GeForce GTX 460 1GB. (explain)
Pixel RateThe Radeon HD 6870 is a lot (approximately 33%) better at AA than the GeForce GTX 460 1GB, and capable of handling higher screen 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: Memory bandwidth is the maximum amount of data (counted in megabytes per second) that can be transported across the external memory interface in a second. The number is worked out by multiplying the interface width by its memory speed. In the case of DDR type RAM, the result should be multiplied by 2 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 AA, HDR and higher screen resolutions.
Texel Rate: Texel rate is the maximum number of texture map elements (texels) that can be applied per second. This figure is calculated by multiplying the total amount of texture units of the card by the core clock speed of the chip. The better this number, the better the video card will be at handling 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 can possibly write to the local memory per second - measured in millions of pixels per second. The figure is worked out by multiplying the number of ROPs 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 output rate is also dependant on quite a few other factors, most notably the memory bandwidth of the card - the lower the memory bandwidth is, the lower the ability to get to the max fill rate.