Compare any two graphics cards:
GeForce 8800 GTS (G80) 640MB vs GeForce 9600 GSO 1.5GB
IntroThe GeForce 8800 GTS (G80) 640MB comes with a core clock frequency of 513 MHz and a GDDR3 memory frequency of 792 MHz. It also makes use of a 320-bit bus, and makes use of a 90 nm design. It is comprised of 96 SPUs, 48 TAUs, and 20 ROPs.
Compare those specifications to the GeForce 9600 GSO 1.5GB, which makes use of a 65 nm design. nVidia has clocked the core speed at 550 MHz. The GDDR3 RAM works at a frequency of 800 MHz on this particular model. It features 96 SPUs along with 48 TAUs and 12 Rasterization Operator Units.
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
As far as performance goes, the GeForce 8800 GTS (G80) 640MB should theoretically be a lot better than the GeForce 9600 GSO 1.5GB in general. (explain)
Texel RateThe GeForce 9600 GSO 1.5GB will be a little bit (about 7%) faster with regards to anisotropic filtering than the GeForce 8800 GTS (G80) 640MB. (explain)
Pixel RateThe GeForce 8800 GTS (G80) 640MB is a lot (approximately 55%) better at anti-aliasing than the GeForce 9600 GSO 1.5GB, and should be capable of handling higher screen resolutions while still performing well. (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.
Memory Bandwidth: Bandwidth is the max amount of data (measured in MB per second) that can be transferred past the external memory interface in one second. It's calculated by multiplying the card's bus width by its memory speed. If the card has DDR RAM, the result should be multiplied by 2 once again. If DDR5, multiply by 4 instead. The better the bandwidth is, the better the card will be in general. It especially helps with AA, HDR and high resolutions.
Texel Rate: Texel rate is the maximum amount of texture map elements (texels) that are processed in one second. This number is worked out by multiplying the total amount of texture units of the card by the core clock speed of the chip. The higher the texel rate, the better the video card will be at texture filtering (anisotropic filtering - AF). It is measured in millions of texels in one second.
Pixel Rate: Pixel rate is the maximum amount of pixels that the graphics chip could possibly record to the local memory in one second - measured in millions of pixels per second. The number is worked out by multiplying the amount of Raster Operations Pipelines by the the core speed of the card. ROPs (Raster Operations Pipelines - also sometimes called Render Output Units) are responsible for filling the screen with pixels (the image). The actual pixel fill rate also depends on lots of other factors, most notably the memory bandwidth of the card - the lower the memory bandwidth is, the lower the ability to get to the maximum fill rate.