Compare any two graphics cards:
GeForce GTX 650 vs Radeon HD 4850 512MB
IntroThe GeForce GTX 650 uses a 28 nm design. nVidia has clocked the core speed at 1058 MHz. The GDDR5 RAM runs at a frequency of 1250 MHz on this model. It features 384 SPUs as well as 32 TAUs and 16 ROPs.
Compare those specifications to the Radeon HD 4850 512MB, which comes with a core clock frequency of 625 MHz and a GDDR3 memory frequency of 993 MHz. It also makes use of a 256-bit bus, and uses a 55 nm design. It is comprised of 800(160x5) SPUs, 40 Texture Address Units, and 16 ROPs.
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
Theoretically speaking, the GeForce GTX 650 will be 26% quicker than the Radeon HD 4850 512MB overall, because of its greater data rate. (explain)
Texel RateThe GeForce GTX 650 should be quite a bit (approximately 35%) better at AF 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 will be capable of handling higher screen 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.
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 largest amount of data (counted in MB per second) that can be moved over the external memory interface within a second. The number is worked out by multiplying the card's interface width by its memory clock speed. In the case of DDR RAM, it should be multiplied by 2 once again. If DDR5, multiply by 4 instead. The better the bandwidth is, the faster the card will be in general. It especially helps with AA, High Dynamic Range and higher screen resolutions.
Texel Rate: Texel rate is the maximum amount of texture map elements (texels) that can be applied per second. This is worked out 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 video card will be at texture filtering (anisotropic filtering - AF). It is measured in millions of texels applied per second.
Pixel Rate: Pixel rate is the maximum number of pixels the graphics card could possibly write to its local memory in a second - measured in millions of pixels per second. The number is calculated by multiplying the amount of Render Output Units by the the card's clock speed. ROPs (Raster Operations Pipelines - also called Render Output Units) are responsible for filling the screen with pixels (the image). The actual pixel fill rate also depends on quite a few other factors, most notably the memory bandwidth of the card - the lower the memory bandwidth is, the lower the ability to get to the max fill rate.