Compare any two graphics cards:
GeForce 8500 GT vs GeForce 8600 GS (OEM)
IntroThe GeForce 8500 GT comes with clock speeds of 450 MHz on the GPU, and 400 MHz on the 512 MB of DDR2 memory. It features 16 SPUs along with 8 Texture Address Units and 4 ROPs.
Compare that to the GeForce 8600 GS (OEM), which features a clock speed of 540 MHz and a DDR2 memory speed of 400 MHz. It also uses a 128-bit memory bus, and uses a 80 nm design. It is made up of 32 SPUs, 16 Texture Address Units, and 8 ROPs.
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
Both cards have exactly the same memory bandwidth, so theoretically they should have the same performance. (explain)
Texel RateThe GeForce 8600 GS (OEM) will be a lot (about 140%) better at anisotropic filtering than the GeForce 8500 GT. (explain)
Pixel RateThe GeForce 8600 GS (OEM) is much (about 140%) better at full screen anti-aliasing than the GeForce 8500 GT, and will be able to handle higher screen resolutions without losing too much performance. (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 (in units of megabytes per second) that can be transported past the external memory interface within a second. The number is calculated by multiplying the card's interface width by its memory clock speed. If it uses DDR RAM, it must be multiplied by 2 once again. If DDR5, multiply by ANOTHER 2x. The better the memory bandwidth, the better the card will be in general. It especially helps with anti-aliasing, HDR and high resolutions.
Texel Rate: Texel rate is the maximum number of texture map elements (texels) that are applied per second. This number is calculated by multiplying the total amount of texture units by the core speed of the chip. The higher this number, the better the graphics card will be at texture filtering (anisotropic filtering - AF). It is measured in millions of texels per second.
Pixel Rate: Pixel rate is the maximum amount of pixels that the graphics chip can possibly record to the local memory per second - measured in millions of pixels per second. Pixel rate is worked out by multiplying the number of Raster Operations Pipelines by the the core clock speed. ROPs (Raster Operations Pipelines - also called Render Output Units) are responsible for drawing the pixels (image) on the screen. The actual pixel rate also depends on many other factors, most notably the memory bandwidth of the card - the lower the bandwidth is, the lower the ability to get to the maximum fill rate.