Compare any two graphics cards:
GeForce GTX 660 vs Radeon HD 5770
IntroThe GeForce GTX 660 features a GPU core 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 TAUs, and 24 ROPs.
Compare that to the Radeon HD 5770, which comes with GPU clock speed of 850 MHz, and 1024 MB of GDDR5 RAM running at 1200 MHz through a 128-bit bus. It also is comprised of 800(160x5) Stream Processors, 40 Texture Address Units, and 16 ROPs.
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
In theory, the GeForce GTX 660 is 88% faster than the Radeon HD 5770 in general, due to its greater data rate. (explain)
Texel RateThe GeForce GTX 660 is much (about 131%) faster with regards to AF than the Radeon HD 5770. (explain)
Pixel RateIf using lots of anti-aliasing is important to you, then the GeForce GTX 660 is superior to the Radeon HD 5770, and very much so. (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 data (measured in MB per second) that can be moved past the external memory interface within a second. The number is calculated by multiplying the interface width by its memory clock speed. In the case of DDR memory, it must be multiplied by 2 again. If DDR5, multiply by 4 instead. The better the 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 processed in one second. This figure is worked out by multiplying the total texture units by the core speed of the chip. The better this number, the better the 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 maximum number of pixels that the graphics card could possibly record to the local memory in one second - measured in millions of pixels per second. Pixel rate is worked out by multiplying the amount of colour ROPs by the the core clock speed. ROPs (Raster Operations Pipelines - also sometimes called Render Output Units) are responsible for drawing the pixels (image) on the screen. The actual pixel rate is also dependant on many other factors, most notably the memory bandwidth of the card - the lower the bandwidth is, the lower the ability to get to the maximum fill rate.