Compare any two graphics cards:
Geforce GTX 680 vs Radeon HD 7870
IntroThe Geforce GTX 680 features a GPU clock speed of 1006 MHz, and the 2048 MB of GDDR5 RAM is set to run at 1502 MHz through a 256-bit bus. It also features 1536 SPUs, 128 Texture Address Units, and 32 Raster Operation Units.
Compare those specifications to the Radeon HD 7870, which features a core clock frequency of 1000 MHz and a GDDR5 memory frequency of 1200 MHz. It also makes use of a 256-bit memory bus, and makes use of a 28 nm design. It features 1280 SPUs, 80 TAUs, and 32 Raster Operation Units.
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
The Geforce GTX 680, in theory, should perform quite a bit faster than the Radeon HD 7870 in general. (explain)
Texel RateThe Geforce GTX 680 should be quite a bit (approximately 61%) more effective at AF than the Radeon HD 7870. (explain)
Pixel RateIf using lots of anti-aliasing is important to you, then the Geforce GTX 680 is the winner, but only just. (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 maximum amount of data (counted in MB per second) that can be transferred across the external memory interface in a second. It's worked out by multiplying the card's bus width by its memory speed. If the card has DDR type RAM, it should be multiplied by 2 again. If DDR5, multiply by 4 instead. The better the bandwidth is, the faster 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 figure is calculated by multiplying the total amount of texture units by the core speed of the chip. The higher this number, the better the card will be at handling texture filtering (anisotropic filtering - AF). It is measured in millions of texels processed in a second.
Pixel Rate: Pixel rate is the most pixels that the graphics chip could possibly record to its local memory in one second - measured in millions of pixels per second. The figure is worked out by multiplying the number of colour ROPs by the the card's clock speed. 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 fill rate also depends on many other factors, especially the memory bandwidth of the card - the lower the memory bandwidth is, the lower the potential to get to the max fill rate.