Compare any two graphics cards:
GeForce GTX 295 vs Radeon HD 6870
IntroThe GeForce GTX 295 features core speeds of 576 MHz on the GPU, and 999 MHz on the 896 MB of GDDR3 memory. It features 240 SPUs along with 80 Texture Address Units and 28 ROPs.
Compare that to the Radeon HD 6870, which makes use of a 40 nm design. AMD has set the core frequency at 900 MHz. The GDDR5 RAM is set to run at a frequency of 1050 MHz on this specific model. It features 1120 SPUs along with 56 TAUs and 32 ROPs.
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
As far as performance goes, the GeForce GTX 295 should in theory be a lot superior to the Radeon HD 6870 overall. (explain)
Texel RateThe GeForce GTX 295 should be quite a bit (more or less 83%) more effective at AF than the Radeon HD 6870. (explain)
Pixel RateThe GeForce GTX 295 will be a little bit (about 12%) more effective at full screen anti-aliasing than the Radeon HD 6870, and also 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.
One or more cards in this comparison are multi-core. This means that their bandwidth, texel and pixel rates are theoretically doubled - this does not mean the card will actually perform twice as fast, but only that it should in theory be able to. Actual game benchmarks will give a more accurate idea of what it's capable of.
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 max amount of data (in units of megabytes per second) that can be transported across the external memory interface in a second. The number is calculated by multiplying the bus width by the speed of its memory. In the case of DDR RAM, the result should be multiplied by 2 again. If it uses DDR5, multiply by ANOTHER 2x. The better the card's memory bandwidth, the better the card will be in general. It especially helps with AA, HDR and high resolutions.
Texel Rate: Texel rate is the maximum number of texture map elements (texels) that can be processed per second. This is calculated by multiplying the total number of texture units by the core clock speed of the chip. The higher this number, the better the graphics 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 number of pixels the video card could possibly write to its local memory in a second - measured in millions of pixels per second. The number is calculated by multiplying the amount of colour ROPs by the the core clock speed. ROPs (Raster Operations Pipelines - also called Render Output Units) are responsible for filling the screen with pixels (the image). The actual pixel fill rate also depends on many other factors, most notably the memory bandwidth of the card - the lower the memory bandwidth is, the lower the ability to reach the max fill rate.