Compare any two graphics cards:
GeForce GTX 650 vs Radeon HD 4850 512MB
IntroThe GeForce GTX 650 features clock speeds of 1058 MHz on the GPU, and 1250 MHz on the 1024 MB of GDDR5 memory. It features 384 SPUs as well as 32 Texture Address Units and 16 Rasterization Operator Units.
Compare all that to the Radeon HD 4850 512MB, which comes with a core clock speed of 625 MHz and a GDDR3 memory speed of 993 MHz. It also features a 256-bit bus, and makes use of a 55 nm design. It is comprised of 800(160x5) SPUs, 40 Texture Address Units, and 16 Raster Operation Units.
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
In theory, the GeForce GTX 650 is 26% quicker than the Radeon HD 4850 512MB in general, because of its higher bandwidth. (explain)
Texel RateThe GeForce GTX 650 should be a lot (about 35%) better at anisotropic filtering than the Radeon HD 4850 512MB. (explain)
Pixel RateThe GeForce GTX 650 will be much (about 69%) faster with regards to FSAA than the Radeon HD 4850 512MB, and also should be able to handle higher screen resolutions without losing too much performance. (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 information (in units of megabytes per second) that can be moved across the external memory interface in a second. The number is calculated by multiplying the card's bus width by its memory clock speed. In the case of DDR type RAM, it should be multiplied by 2 once again. If it uses DDR5, multiply by 4 instead. The higher the card's memory bandwidth, 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 in one second. This figure is calculated by multiplying the total amount of texture units of the card by the core clock speed of the chip. The higher the texel rate, the better the video card will be at handling texture filtering (anisotropic filtering - AF). It is measured in millions of texels per second.
Pixel Rate: Pixel rate is the maximum number of pixels the graphics card can possibly record to the local memory in one second - measured in millions of pixels per second. The number is calculated by multiplying the amount of Raster Operations Pipelines by the clock speed of the card. ROPs (Raster Operations Pipelines - aka Render Output Units) are responsible for filling the screen with pixels (the image). The actual pixel rate is also dependant on lots of other factors, especially the memory bandwidth of the card - the lower the memory bandwidth is, the lower the ability to reach the maximum fill rate.