Compare any two graphics cards:
GeForce GTX 650 vs Radeon HD 7850
IntroThe GeForce GTX 650 comes with a GPU core clock 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 Texture Address Units, and 16 Raster Operation Units.
Compare all that to the Radeon HD 7850, which comes with a core clock speed of 860 MHz and a GDDR5 memory frequency of 1200 MHz. It also uses a 256-bit bus, and uses a 28 nm design. It is comprised of 1024 SPUs, 64 TAUs, and 32 ROPs.
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
As far as performance goes, the Radeon HD 7850 should theoretically be much better than the GeForce GTX 650 overall. (explain)
Texel RateThe Radeon HD 7850 is quite a bit (approximately 63%) more effective at anisotropic filtering than the GeForce GTX 650. (explain)
Pixel RateIf running with a high screen resolution is important to you, then the Radeon HD 7850 is the winner, 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 (counted in MB per second) that can be transported over the external memory interface in one second. It is calculated by multiplying the interface width by its memory clock speed. If it uses DDR RAM, it must be multiplied by 2 again. If DDR5, multiply by ANOTHER 2x. The better the memory bandwidth, the better the card will be in general. It especially helps with AA, HDR and high resolutions.
Texel Rate: Texel rate is the maximum texture map elements (texels) that can be processed per second. This is worked out by multiplying the total texture units by the core clock 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 applied in one second.
Pixel Rate: Pixel rate is the maximum amount of pixels that the graphics card could possibly write to the local memory in a second - measured in millions of pixels per second. Pixel rate is worked out by multiplying the amount of colour ROPs by the the card's clock speed. ROPs (Raster Operations Pipelines - aka Render Output Units) are responsible for drawing the pixels (image) on the screen. The actual pixel rate also depends on many other factors, most notably the memory bandwidth - the lower the bandwidth is, the lower the potential to get to the max fill rate.