Compare any two graphics cards:
GeForce GT 430 vs GeForce GT 640 DDR3
IntroThe GeForce GT 430 comes with a GPU core clock speed of 700 MHz, and the 512 MB of GDDR3 memory is set to run at 900 MHz through a 128-bit bus. It also features 96 Stream Processors, 16 Texture Address Units, and 4 Raster Operation Units.
Compare those specs to the GeForce GT 640 DDR3, which 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 Texture Address Units and 16 ROPs.
(No game benchmarks for this combination yet.)
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
In theory, the GeForce GT 640 DDR3 is 98% faster than the GeForce GT 430 in general, due to its greater data rate. (explain)
Texel RateThe GeForce GT 640 DDR3 should be a lot (about 157%) better at anisotropic filtering than the GeForce GT 430. (explain)
Pixel RateThe GeForce GT 640 DDR3 will be quite a bit (approximately 414%) more effective at anti-aliasing than the GeForce GT 430, and also should be able to handle higher resolutions while still performing well. (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 information (measured in MB per second) that can be transported across the external memory interface in one second. It is calculated by multiplying the interface width by its memory speed. If the card has DDR RAM, it must be multiplied by 2 once again. If it uses DDR5, multiply by ANOTHER 2x. The higher 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 can be processed in one second. This number is calculated by multiplying the total number of texture units of the card by the core speed of the chip. The higher the texel rate, the better the video card will be at handling texture filtering (anisotropic filtering - AF). It is measured in millions of texels processed per second.
Pixel Rate: Pixel rate is the maximum amount of pixels that the graphics chip could possibly write to the local memory per second - measured in millions of pixels per second. Pixel rate is worked out by multiplying the number of ROPs by the the core clock speed. ROPs (Raster Operations Pipelines - aka Render Output Units) are responsible for filling the screen with pixels (the image). The actual pixel fill rate is also dependant on lots of other factors, most notably the memory bandwidth of the card - the lower the bandwidth is, the lower the potential to get to the max fill rate.