Compare any two graphics cards:
GeForce GTX 650 vs Radeon HD 6850
IntroThe GeForce GTX 650 comes with a GPU core speed of 1058 MHz, and the 2048 MB of GDDR5 memory runs at 1250 MHz through a 128-bit bus. It also is made up of 384 SPUs, 32 TAUs, and 16 Raster Operation Units.
Compare that to the Radeon HD 6850, which features a GPU core clock speed of 775 MHz, and 1024 MB of GDDR5 RAM running at 1000 MHz through a 256-bit bus. It also features 960 Stream Processors, 48 TAUs, and 32 ROPs.
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
Theoretically speaking, the Radeon HD 6850 is 60% faster than the GeForce GTX 650 overall, because of its higher data rate. (explain)
Texel RateThe Radeon HD 6850 should be a small bit (approximately 10%) more effective at AF than the GeForce GTX 650. (explain)
Pixel RateThe Radeon HD 6850 should be much (about 47%) faster with regards to full screen anti-aliasing than the GeForce GTX 650, and should be capable of handling higher resolutions better. (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: Bandwidth is the max amount of data (measured in megabytes per second) that can be transferred across the external memory interface within a second. It's worked out by multiplying the bus width by its memory speed. If it uses DDR type memory, it must be multiplied by 2 once again. If it uses DDR5, multiply by ANOTHER 2x. The better the bandwidth is, the better the card will be in general. It especially helps with AA, HDR and high resolutions.
Texel Rate: Texel rate is the maximum number of texture map elements (texels) that can be applied per second. This is calculated by multiplying the total amount of texture units of the card by the core speed of the chip. The better the texel rate, the better the graphics 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 card could possibly write to its local memory per second - measured in millions of pixels per second. The number is worked out by multiplying the amount of Raster Operations Pipelines by the the core clock speed. ROPs (Raster Operations Pipelines - also sometimes called Render Output Units) are responsible for filling the screen with pixels (the image). The actual pixel output rate also depends on lots of other factors, especially the memory bandwidth - the lower the memory bandwidth is, the lower the ability to get to the maximum fill rate.