Compare any two graphics cards:
GeForce GT 640 DDR3 vs GeForce GTX 580 3GB
IntroThe GeForce GT 640 DDR3 makes use of a 28 nm design. nVidia has clocked the core speed at 900 MHz. The DDR3 memory works at a frequency of 1782 MHz on this particular model. It features 384 SPUs as well as 32 TAUs and 16 ROPs.
Compare those specs to the GeForce GTX 580 3GB, which makes use of a 40 nm design. nVidia has set the core speed at 772 MHz. The GDDR5 RAM is set to run at a frequency of 1002 MHz on this particular model. It features 512 SPUs as well as 64 TAUs and 48 ROPs.
(No game benchmarks for this combination yet.)
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
As far as performance goes, the GeForce GTX 580 3GB should in theory be quite a bit superior to the GeForce GT 640 DDR3 overall. (explain)
Texel RateThe GeForce GTX 580 3GB will be much (more or less 72%) more effective at texture filtering than the GeForce GT 640 DDR3. (explain)
Pixel RateThe GeForce GTX 580 3GB is quite a bit (about 157%) better at AA than the GeForce GT 640 DDR3, and capable of handling 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.
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 largest amount of information (counted in megabytes per second) that can be moved across the external memory interface in a second. It is calculated by multiplying the interface width by the speed of its memory. In the case of DDR type RAM, the result should be multiplied by 2 once again. If DDR5, multiply by ANOTHER 2x. The higher the card's 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 applied per second. This is worked out by multiplying the total number of texture units by the core clock speed of the chip. The better the texel rate, the better the video card will be at texture filtering (anisotropic filtering - AF). It is measured in millions of texels per second.
Pixel Rate: Pixel rate is the maximum number of pixels the graphics card can possibly write to the local memory in a second - measured in millions of pixels per second. The number is calculated by multiplying the amount of colour 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 rate is also dependant on many other factors, especially the memory bandwidth of the card - the lower the bandwidth is, the lower the ability to reach the maximum fill rate.