Compare any two graphics cards:
GeForce GTX 650 vs Radeon HD 6850
IntroThe GeForce GTX 650 comes with a GPU clock speed of 1058 MHz, and the 2048 MB of GDDR5 memory runs at 1250 MHz through a 128-bit bus. It also features 384 SPUs, 32 TAUs, and 16 ROPs.
Compare all that to the Radeon HD 6850, which comes with a core clock frequency of 775 MHz and a GDDR5 memory frequency of 1000 MHz. It also uses a 256-bit bus, and uses a 40 nm design. It is made up of 960 SPUs, 48 Texture Address Units, and 32 Raster Operation Units.
(No game benchmarks for this combination yet.)
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
The Radeon HD 6850, in theory, should be much faster than the GeForce GTX 650 overall. (explain)
Texel RateThe Radeon HD 6850 is a little bit (about 10%) better at anisotropic filtering than the GeForce GTX 650. (explain)
Pixel RateIf using lots of anti-aliasing is important to you, then the Radeon HD 6850 is a better choice, 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: Bandwidth is the largest amount of information (in units of megabytes per second) that can be moved across the external memory interface in a second. It's worked out by multiplying the bus width by its memory speed. If the card has DDR type RAM, it should be multiplied by 2 once 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, High Dynamic Range and high resolutions.
Texel Rate: Texel rate is the maximum amount of texture map elements (texels) that are processed in one second. This is worked out by multiplying the total number of texture units by the core clock speed of the chip. The better this number, the better the video card will be at handling texture filtering (anisotropic filtering - AF). It is measured in millions of texels processed per second.
Pixel Rate: Pixel rate is the most pixels the graphics card can possibly write to the local memory in a second - measured in millions of pixels per second. The figure is calculated by multiplying the amount of ROPs by the the card's clock speed. ROPs (Raster Operations Pipelines - also sometimes called Render Output Units) are responsible for outputting the pixels (image) to the screen. The actual pixel rate also depends on many other factors, most notably the memory bandwidth of the card - the lower the bandwidth is, the lower the potential to reach the maximum fill rate.