Compare any two graphics cards:
GeForce GT 640 DDR3 vs GeForce GTX 260
IntroThe GeForce GT 640 DDR3 makes use of a 28 nm design. nVidia has set the core speed at 900 MHz. The DDR3 RAM works at a speed of 1782 MHz on this particular model. It features 384 SPUs along with 32 TAUs and 16 Rasterization Operator Units.
Compare that to the GeForce GTX 260, which has a GPU core clock speed of 576 MHz, and 896 MB of GDDR3 memory set to run at 999 MHz through a 448-bit bus. It also features 192 Stream Processors, 64 Texture Address Units, and 28 Raster Operation Units.
(No game benchmarks for this combination yet.)
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
In theory, the GeForce GTX 260 is 96% faster than the GeForce GT 640 DDR3 overall, due to its greater data rate. (explain)
Texel RateThe GeForce GTX 260 should be much (more or less 28%) better at AF than the GeForce GT 640 DDR3. (explain)
Pixel RateThe GeForce GTX 260 should be a small bit (approximately 12%) faster with regards to FSAA than the GeForce GT 640 DDR3, and also capable of handling higher 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.
Price ComparisonPlease note that the price comparisons are based on search keywords, and might not be the exact same card listed on this page. We have no control over the accuracy of their search results.
Memory Bandwidth: Bandwidth is the max amount of data (counted in megabytes per second) that can be moved over the external memory interface in one second. It's calculated by multiplying the interface width by its memory speed. In the case of DDR RAM, it must be multiplied by 2 once again. If it uses 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 higher screen resolutions.
Texel Rate: Texel rate is the maximum texture map elements (texels) that are processed in one second. This figure is worked out by multiplying the total number of texture units by the core clock speed of the chip. The higher this number, the better the card will be at texture filtering (anisotropic filtering - AF). It is measured in millions of texels processed in one second.
Pixel Rate: Pixel rate is the maximum number of pixels the graphics card could possibly record to the local memory in one second - measured in millions of pixels per second. The number is worked out by multiplying the number of ROPs by the the card's clock speed. ROPs (Raster Operations Pipelines - aka Render Output Units) are responsible for drawing the pixels (image) on the screen. The actual pixel output rate also depends on lots of other factors, especially the memory bandwidth of the card - the lower the bandwidth is, the lower the potential to get to the maximum fill rate.