Compare any two graphics cards:
GeForce 8800 GTS (G92) vs GeForce GT 640 DDR3
IntroThe GeForce 8800 GTS (G92) has a GPU core clock speed of 650 MHz, and the 512 MB of GDDR3 memory runs at 970 MHz through a 256-bit bus. It also is comprised of 128 SPUs, 64 Texture Address Units, and 16 ROPs.
Compare all of that to the GeForce GT 640 DDR3, which has core speeds of 900 MHz on the GPU, and 1782 MHz on the 2048 MB of DDR3 RAM. It features 384 SPUs as well as 32 Texture Address Units and 16 ROPs.
(No game benchmarks for this combination yet.)
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
Performance-wise, the GeForce 8800 GTS (G92) should in theory be a little bit superior to the GeForce GT 640 DDR3 in general. (explain)
Texel RateThe GeForce 8800 GTS (G92) should be quite a bit (approximately 44%) better at AF than the GeForce GT 640 DDR3. (explain)
Pixel RateThe GeForce GT 640 DDR3 is a lot (approximately 38%) faster with regards to anti-aliasing than the GeForce 8800 GTS (G92), and will be capable of handling higher screen resolutions without slowing down too much. (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 (in units of megabytes per second) that can be moved across the external memory interface in a second. The number is worked out by multiplying the card's interface width by its memory speed. If it uses DDR type RAM, it should be multiplied by 2 once again. If DDR5, multiply by 4 instead. The higher the memory bandwidth, the better the card will be in general. It especially helps with anti-aliasing, High Dynamic Range and higher screen resolutions.
Texel Rate: Texel rate is the maximum number of texture map elements (texels) that can be processed per second. This number is worked out by multiplying the total number 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 processed per second.
Pixel Rate: Pixel rate is the maximum number of pixels that the graphics card could possibly record to its local memory per second - measured in millions of pixels per second. The figure is worked out by multiplying the amount of Raster Operations Pipelines by the the core clock speed. ROPs (Raster Operations Pipelines - sometimes also referred to as Render Output Units) are responsible for filling the screen with pixels (the image). The actual pixel fill rate also depends on many other factors, especially the memory bandwidth - the lower the memory bandwidth is, the lower the ability to reach the maximum fill rate.