Compare any two graphics cards:
GeForce GTX 285 2GB vs Radeon HD 6850
IntroThe GeForce GTX 285 2GB comes with clock speeds of 648 MHz on the GPU, and 1242 MHz on the 2048 MB of GDDR3 memory. It features 240 SPUs as well as 80 Texture Address Units and 32 ROPs.
Compare that to the Radeon HD 6850, which features GPU core speed of 775 MHz, and 1024 MB of GDDR5 memory running at 1000 MHz through a 256-bit bus. It also is comprised of 960 Stream Processors, 48 Texture Address Units, and 32 Raster Operation Units.
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
The GeForce GTX 285 2GB, in theory, should be quite a bit faster than the Radeon HD 6850 in general. (explain)
Texel RateThe GeForce GTX 285 2GB should be a lot (more or less 39%) faster with regards to AF than the Radeon HD 6850. (explain)
Pixel RateIf using high levels of AA is important to you, then the Radeon HD 6850 is the winner, not by a very large margin though. (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 transported past the external memory interface within a second. It is worked out by multiplying the card's bus width by its memory speed. If it uses DDR RAM, it should be multiplied by 2 once again. If it uses DDR5, multiply by ANOTHER 2x. The higher the memory bandwidth, 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 are applied in one second. This is calculated by multiplying the total texture units by the core speed of the chip. The higher this number, the better the video card will be at texture filtering (anisotropic filtering - AF). It is measured in millions of texels processed in a second.
Pixel Rate: Pixel rate is the most pixels the graphics card can possibly write to the local memory in one second - measured in millions of pixels per second. The number is worked out by multiplying the number of colour ROPs by the the card's clock speed. ROPs (Raster Operations Pipelines - also called Render Output Units) are responsible for drawing the pixels (image) on the screen. The actual pixel output rate also depends on quite a few other factors, most notably the memory bandwidth - the lower the memory bandwidth is, the lower the potential to reach the maximum fill rate.