Compare any two graphics cards:
GeForce GT 430 vs GeForce GT 640 DDR3
IntroThe GeForce GT 430 uses a 40 nm design. nVidia has set the core frequency at 700 MHz. The GDDR3 RAM works at a speed of 900 MHz on this specific model. It features 96 SPUs along with 16 Texture Address Units and 4 Rasterization Operator Units.
Compare those specifications to the GeForce GT 640 DDR3, which has a core clock frequency of 900 MHz and a DDR3 memory speed of 1782 MHz. It also uses a 128-bit bus, and uses a 28 nm design. It is comprised of 384 SPUs, 32 TAUs, and 16 ROPs.
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
The GeForce GT 640 DDR3, in theory, should be much faster than the GeForce GT 430 overall. (explain)
Texel RateThe GeForce GT 640 DDR3 is much (about 157%) faster with regards to texture filtering than the GeForce GT 430. (explain)
Pixel RateThe GeForce GT 640 DDR3 will be much (approximately 414%) better at AA than the GeForce GT 430, and also will be capable of handling higher 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 largest amount of data (counted in MB per second) that can be transferred over the external memory interface within a second. It's calculated by multiplying the card's bus width by the speed of its memory. If the card has DDR type memory, it must be multiplied by 2 once again. If DDR5, multiply by ANOTHER 2x. The higher the card's 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 can be applied in one second. This is calculated by multiplying the total texture units by the core clock speed of the chip. The better the texel rate, the better the graphics card will be at handling texture filtering (anisotropic filtering - AF). It is measured in millions of texels in one second.
Pixel Rate: Pixel rate is the most 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 Render Output Units by the the core speed of the card. ROPs (Raster Operations Pipelines - also sometimes called Render Output Units) are responsible for outputting the pixels (image) to the screen. The actual pixel rate also depends on quite a few other factors, especially the memory bandwidth of the card - the lower the memory bandwidth is, the lower the ability to reach the maximum fill rate.