Compare any two graphics cards:
GeForce 8800 GT 1GB vs GeForce GTX 650
IntroThe GeForce 8800 GT 1GB features a GPU core speed of 600 MHz, and the 1024 MB of GDDR3 RAM runs at 900 MHz through a 256-bit bus. It also is made up of 112 SPUs, 56 TAUs, and 16 Raster Operation Units.
Compare that to the GeForce GTX 650, which comes with a GPU core clock speed of 1058 MHz, and 2048 MB of GDDR5 memory running at 1250 MHz through a 128-bit bus. It also features 384 SPUs, 32 Texture Address Units, and 16 ROPs.
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
In theory, the GeForce GTX 650 is 39% quicker than the GeForce 8800 GT 1GB overall, due to its greater bandwidth. (explain)
Texel RateThe GeForce GTX 650 is just a bit (about 1%) better at anisotropic filtering than the GeForce 8800 GT 1GB. (explain)
Pixel RateIf running with lots of anti-aliasing is important to you, then the GeForce GTX 650 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: Memory bandwidth is the max amount of information (in units of megabytes per second) that can be transferred across the external memory interface within a second. It is worked out by multiplying the bus width by its memory clock speed. In the case of DDR type RAM, it must be multiplied by 2 once again. If DDR5, multiply by ANOTHER 2x. The higher the card's memory bandwidth, the better the card will be in general. It especially helps with AA, HDR and high resolutions.
Texel Rate: Texel rate is the maximum number of texture map elements (texels) that are processed per second. This is worked out by multiplying the total number of texture units of the card by the core clock speed of the chip. The higher this number, the better the 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 most pixels that the graphics card can possibly write to its local memory in one second - measured in millions of pixels per second. Pixel rate is worked out by multiplying the number of Render Output Units by the the core speed of the card. 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 rate also depends on quite a few other factors, especially the memory bandwidth of the card - the lower the memory bandwidth is, the lower the potential to reach the maximum fill rate.