Compare any two graphics cards:
GeForce 8800 GT 512MB vs GeForce 9800 GT 1GB
IntroThe GeForce 8800 GT 512MB has a GPU core clock speed of 600 MHz, and the 512 MB of GDDR3 memory is set to run at 900 MHz through a 256-bit bus. It also is comprised of 112 Stream Processors, 56 Texture Address Units, and 16 Raster Operation Units.
Compare those specifications to the GeForce 9800 GT 1GB, which makes use of a 65/55 nm design. nVidia has set the core speed at 600 MHz. The GDDR3 RAM runs at a frequency of 900 MHz on this specific model. It features 112 SPUs as well as 56 Texture Address Units and 16 ROPs.
Power Usage and Theoretical BenchmarksBoth cards have the same power consumption.
Both cards have the exact same bandwidth, so theoretically they should perform exactly the same. (explain)
Texel RateBoth cards have the exact same texel fill rate, so theoretically they should be equally good at at anisotropic filtering. (explain)
Pixel RateBoth cards have exactly the same pixel rate, so theoretically they should perform equally good at at anti-aliasing, and be capable of handling the same resolutions. (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 past the external memory interface in a second. It is calculated by multiplying the card's interface width by its memory clock speed. If the card has DDR type memory, it must be multiplied by 2 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 AA, High Dynamic Range and higher screen resolutions.
Texel Rate: Texel rate is the maximum texture map elements (texels) that can be processed in one second. This figure is calculated by multiplying the total number of texture units of the card by the core speed of the chip. The higher the texel rate, the better the video card will be at handling texture filtering (anisotropic filtering - AF). It is measured in millions of texels applied in one second.
Pixel Rate: Pixel rate is the maximum number of pixels the video card could possibly record to its local memory in one second - measured in millions of pixels per second. Pixel rate is worked out by multiplying the amount of Raster Operations Pipelines by the the core clock speed. ROPs (Raster Operations Pipelines - aka Render Output Units) are responsible for filling the screen with pixels (the image). The actual pixel rate is also dependant on lots of other factors, most notably the memory bandwidth of the card - the lower the memory bandwidth is, the lower the ability to reach the maximum fill rate.