Compare any two graphics cards:
GeForce GTX 650 vs GeForce GTX 660
IntroThe GeForce GTX 650 features a GPU clock speed of 1058 MHz, and the 2048 MB of GDDR5 memory is set to run at 1250 MHz through a 128-bit bus. It also is comprised of 384 Stream Processors, 32 TAUs, and 16 Raster Operation Units.
Compare all of that to the GeForce GTX 660, which has a clock speed of 980 MHz and a GDDR5 memory frequency of 1502 MHz. It also uses a 192-bit bus, and makes use of a 28 nm design. It is made up of 960 SPUs, 80 TAUs, and 24 ROPs.
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
As far as performance goes, the GeForce GTX 660 should in theory be quite a bit better than the GeForce GTX 650 in general. (explain)
Texel RateThe GeForce GTX 660 should be a lot (about 132%) better at AF than the GeForce GTX 650. (explain)
Pixel RateIf using a high resolution is important to you, then the GeForce GTX 660 is a better choice, by far. (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 data (counted in MB per second) that can be moved across the external memory interface in a second. It is worked out by multiplying the card's bus width by its memory clock speed. In the case of DDR type memory, it must be multiplied by 2 once again. If DDR5, multiply by 4 instead. The higher the memory bandwidth, the better the card will be in general. It especially helps with anti-aliasing, HDR and higher screen resolutions.
Texel Rate: Texel rate is the maximum amount of texture map elements (texels) that can be processed per second. This figure is calculated by multiplying the total number of texture units by the core speed of the chip. The better the texel rate, the better the graphics card will be at handling texture filtering (anisotropic filtering - AF). It is measured in millions of texels applied in one second.
Pixel Rate: Pixel rate is the maximum amount of pixels that 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 number of Render Output Units by the the core clock speed. ROPs (Raster Operations Pipelines - aka Render Output Units) are responsible for outputting the pixels (image) to the screen. The actual pixel rate is also dependant on quite a few other factors, especially the memory bandwidth - the lower the bandwidth is, the lower the potential to get to the max fill rate.