Compare any two graphics cards:
GeForce 8600 GT 256MB GDDR3 vs GeForce GT 320
IntroThe GeForce 8600 GT 256MB GDDR3 uses a 80 nm design. nVidia has set the core frequency at 540 MHz. The GDDR3 memory runs at a frequency of 700 MHz on this model. It features 32 SPUs as well as 16 Texture Address Units and 8 Rasterization Operator Units.
Compare all that to the GeForce GT 320, which comes with clock speeds of 540 MHz on the GPU, and 790 MHz on the 1024 MB of GDDR3 memory. It features 72 SPUs along with 24 Texture Address Units and 8 Rasterization Operator Units.
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
Performance-wise, the GeForce GT 320 should in theory be just a bit better than the GeForce 8600 GT 256MB GDDR3 overall. (explain)
Texel RateThe GeForce GT 320 is quite a bit (more or less 50%) more effective at texture filtering than the GeForce 8600 GT 256MB GDDR3. (explain)
Pixel RateBoth cards have exactly the same pixel rate, so theoretically they should perform equally good at at AA, and be capable of handling the same screen 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 largest amount of data (measured in megabytes per second) that can be moved across the external memory interface within a second. It is calculated by multiplying the interface width by its memory speed. If the card has DDR type memory, the result should be multiplied by 2 once again. If DDR5, multiply by ANOTHER 2x. The better the memory bandwidth, the faster the card will be in general. It especially helps with AA, High Dynamic Range and high resolutions.
Texel Rate: Texel rate is the maximum texture map elements (texels) that are applied in one second. This is calculated by multiplying the total number of texture units of the card by the core speed of the chip. The better the texel rate, the better the graphics 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 maximum amount of pixels that the graphics card could possibly record to the local memory in one 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 filling the screen with pixels (the image). The actual pixel fill rate also depends on quite a few other factors, most notably the memory bandwidth of the card - the lower the bandwidth is, the lower the potential to get to the maximum fill rate.