Compare any two graphics cards:
GeForce GTX 295 vs Geforce GTX 680
IntroThe GeForce GTX 295 has a GPU core clock speed of 576 MHz, and the 896 MB of GDDR3 RAM is set to run at 999 MHz through a 448-bit bus. It also is comprised of 240 Stream Processors, 80 TAUs, and 28 Raster Operation Units.
Compare that to the Geforce GTX 680, which has core speeds of 1006 MHz on the GPU, and 1502 MHz on the 2048 MB of GDDR5 RAM. It features 1536 SPUs along with 128 Texture Address Units and 32 Rasterization Operator Units.
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
In theory, the GeForce GTX 295 should be a little bit faster than the Geforce GTX 680 overall. (explain)
Texel RateThe Geforce GTX 680 should be a lot (approximately 40%) faster with regards to AF than the GeForce GTX 295. (explain)
Pixel RateIf using a high resolution is important to you, then the GeForce GTX 295 is the winner, though not by far. (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.
One or more cards in this comparison are multi-core. This means that their bandwidth, texel and pixel rates are theoretically doubled - this does not mean the card will actually perform twice as fast, but only that it should in theory be able to. Actual game benchmarks will give a more accurate idea of what it's capable of.
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 largest amount of data (counted in megabytes per second) that can be moved over the external memory interface within a second. It's calculated by multiplying the interface width by its memory clock speed. In the case of DDR type memory, 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, HDR and higher screen resolutions.
Texel Rate: Texel rate is the maximum number of texture map elements (texels) that are applied per second. This is calculated by multiplying the total number of texture units by the core 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 processed per second.
Pixel Rate: Pixel rate is the maximum amount of pixels the video card can possibly record to its local memory per second - measured in millions of pixels per second. Pixel rate is calculated by multiplying the amount of ROPs by the clock speed of the card. ROPs (Raster Operations Pipelines - sometimes also referred to as Render Output Units) are responsible for outputting the pixels (image) to the screen. The actual pixel fill rate also depends on quite a few other factors, especially the memory bandwidth - the lower the bandwidth is, the lower the potential to reach the maximum fill rate.