Compare any two graphics cards:
GeForce 8800 GTS (G92) vs GeForce GT 640 DDR3
IntroThe GeForce 8800 GTS (G92) has a GPU core speed of 650 MHz, and the 512 MB of GDDR3 memory is set to run at 970 MHz through a 256-bit bus. It also is comprised of 128 Stream Processors, 64 TAUs, and 16 ROPs.
Compare those specs to the GeForce GT 640 DDR3, which uses a 28 nm design. nVidia has clocked the core frequency at 900 MHz. The DDR3 RAM runs at a frequency of 1782 MHz on this specific model. It features 384 SPUs along with 32 Texture Address Units and 16 Rasterization Operator Units.
(No game benchmarks for this combination yet.)
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
Theoretically, the GeForce 8800 GTS (G92) should perform a small bit faster than the GeForce GT 640 DDR3 overall. (explain)
Texel RateThe GeForce 8800 GTS (G92) should be a lot (more or less 44%) faster with regards to AF than the GeForce GT 640 DDR3. (explain)
Pixel RateIf running with high levels of AA is important to you, then the GeForce GT 640 DDR3 is superior to the GeForce 8800 GTS (G92), by a large margin. (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: Memory bandwidth is the max amount of information (in units of MB per second) that can be transported across the external memory interface in one second. It's worked out by multiplying the interface width by the speed of its memory. In the case of DDR RAM, it must be multiplied by 2 once again. If it uses DDR5, multiply by 4 instead. The better the card's memory bandwidth, the faster the card will be in general. It especially helps with AA, HDR 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 speed of the chip. The higher the texel rate, the better the card will be at handling texture filtering (anisotropic filtering - AF). It is measured in millions of texels in a second.
Pixel Rate: Pixel rate is the most pixels that the graphics card can possibly record to its local memory in one second - measured in millions of pixels per second. The figure is worked out by multiplying the amount of ROPs by the the core speed of the card. ROPs (Raster Operations Pipelines - sometimes also referred to as Render Output Units) are responsible for filling the screen with pixels (the image). The actual pixel output rate is also dependant on quite a few other factors, most notably the memory bandwidth of the card - the lower the bandwidth is, the lower the ability to reach the maximum fill rate.