Compare any two graphics cards:
GeForce GTX 660 vs Radeon HD 7850
IntroThe GeForce GTX 660 has a GPU clock speed of 980 MHz, and the 2048 MB of GDDR5 memory is set to run at 1502 MHz through a 192-bit bus. It also is made up of 960 SPUs, 80 Texture Address Units, and 24 ROPs.
Compare those specs to the Radeon HD 7850, which makes use of a 28 nm design. AMD has set the core frequency at 860 MHz. The GDDR5 memory is set to run at a frequency of 1200 MHz on this card. It features 1024 SPUs along with 64 TAUs and 32 Rasterization Operator Units.
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
In theory, the Radeon HD 7850 should perform a small bit faster than the GeForce GTX 660 overall. (explain)
Texel RateThe GeForce GTX 660 should be quite a bit (more or less 42%) better at texture filtering than the Radeon HD 7850. (explain)
Pixel RateThe Radeon HD 7850 should be a bit (about 17%) faster with regards to AA than the GeForce GTX 660, and also should be able to handle higher resolutions more effectively. (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 maximum amount of information (measured in megabytes per second) that can be moved over the external memory interface in a second. It's calculated by multiplying the interface width by its memory speed. In the case of DDR type memory, it should be multiplied by 2 again. If it uses DDR5, multiply by 4 instead. The better the card's memory bandwidth, 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 number of texture map elements (texels) that are applied per second. This figure is calculated by multiplying the total amount of texture units by the core speed of the chip. The higher this number, the better the video card will be at handling texture filtering (anisotropic filtering - AF). It is measured in millions of texels processed in one second.
Pixel Rate: Pixel rate is the most pixels that the graphics chip could possibly record to the local memory in a second - measured in millions of pixels per second. The number is calculated by multiplying the number of ROPs by the the card's clock speed. ROPs (Raster Operations Pipelines - sometimes also referred to as Render Output Units) are responsible for drawing the pixels (image) on the screen. The actual pixel output rate is also dependant on lots of other factors, most notably the memory bandwidth - the lower the bandwidth is, the lower the potential to get to the max fill rate.