Compare any two graphics cards:
GeForce GT 430 vs GeForce GT 640 DDR3
IntroThe GeForce GT 430 uses a 40 nm design. nVidia has clocked the core frequency at 700 MHz. The GDDR3 memory runs at a frequency of 900 MHz on this specific card. It features 96 SPUs as well as 16 TAUs and 4 Rasterization Operator Units.
Compare those specs to the GeForce GT 640 DDR3, which uses a 28 nm design. nVidia has set the core speed at 900 MHz. The DDR3 RAM works at a frequency of 1782 MHz on this specific model. It features 384 SPUs as well as 32 Texture Address Units and 16 Rasterization Operator Units.
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
Theoretically, the GeForce GT 640 DDR3 should perform much faster than the GeForce GT 430 overall. (explain)
Texel RateThe GeForce GT 640 DDR3 is quite a bit (about 157%) more effective at anisotropic filtering than the GeForce GT 430. (explain)
Pixel RateThe GeForce GT 640 DDR3 is much (more or less 414%) better at AA than the GeForce GT 430, and should be able to handle higher screen resolutions better. (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 maximum amount of data (counted in MB per second) that can be moved over the external memory interface in one second. It is worked out by multiplying the card's interface width by its memory speed. In the case of DDR memory, it must be multiplied by 2 again. If it uses DDR5, multiply by 4 instead. The higher the memory bandwidth, the faster the card will be in general. It especially helps with AA, High Dynamic Range and higher screen resolutions.
Texel Rate: Texel rate is the maximum texture map elements (texels) that are applied per second. This number is worked out by multiplying the total amount of texture units of the card by the core speed of the chip. The better the texel rate, the better the card will be at texture filtering (anisotropic filtering - AF). It is measured in millions of texels applied in a second.
Pixel Rate: Pixel rate is the maximum number of pixels that the graphics card can possibly write to its local memory in one second - measured in millions of pixels per second. The figure is calculated by multiplying the amount of ROPs by the the core speed of the card. ROPs (Raster Operations Pipelines - aka Render Output Units) are responsible for outputting the pixels (image) to the screen. The actual pixel rate is also dependant on quite a few other factors, especially the memory bandwidth - the lower the bandwidth is, the lower the potential to get to the maximum fill rate.