Compare any two graphics cards:
GeForce GTX 295 vs Geforce GTX 680
IntroThe GeForce GTX 295 comes with a GPU core speed of 576 MHz, and the 896 MB of GDDR3 RAM runs at 999 MHz through a 448-bit bus. It also is made up of 240 Stream Processors, 80 Texture Address Units, and 28 ROPs.
Compare those specs to the Geforce GTX 680, which has GPU core speed of 1006 MHz, and 2048 MB of GDDR5 memory running at 1502 MHz through a 256-bit bus. It also is comprised of 1536 Stream Processors, 128 Texture Address Units, and 32 ROPs.
(No game benchmarks for this combination yet.)
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
In theory, the GeForce GTX 295 should be 16% faster than the Geforce GTX 680 in general, because of its higher data rate. (explain)
Texel RateThe Geforce GTX 680 will be much (about 40%) better at texture filtering than the GeForce GTX 295. (explain)
Pixel RateThe GeForce GTX 295 is a small bit (approximately 0%) more effective at FSAA than the Geforce GTX 680, and should be 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.
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 maximum amount of data (counted in megabytes per second) that can be transported past the external memory interface in one second. It is worked out by multiplying the bus width by the speed of its memory. If the card has DDR type RAM, the result should be multiplied by 2 again. If it uses DDR5, multiply by ANOTHER 2x. The higher the bandwidth is, the better 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 in one second. This number is calculated by multiplying the total amount of texture units by the core speed of the chip. The higher 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 most pixels the graphics card can possibly record to its local memory per second - measured in millions of pixels per second. The number is worked out by multiplying the number of Raster Operations Pipelines by the the card's clock speed. ROPs (Raster Operations Pipelines - also sometimes called Render Output Units) are responsible for outputting the pixels (image) to the screen. The actual pixel output rate is also dependant on many other factors, most notably the memory bandwidth of the card - the lower the memory bandwidth is, the lower the potential to get to the max fill rate.