Compare any two graphics cards:
GeForce 9800 GX2 vs GeForce GTX 260 Core 216
IntroThe GeForce 9800 GX2 features core clock speeds of 600 MHz on the GPU, and 1000 MHz on the 512 MB of GDDR3 memory. It features 128 SPUs as well as 64 Texture Address Units and 16 ROPs.
Compare all of that to the GeForce GTX 260 Core 216, which has clock speeds of 576 MHz on the GPU, and 999 MHz on the 896 MB of GDDR3 RAM. It features 216 SPUs along with 72 TAUs and 28 ROPs.
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
Theoretically speaking, the GeForce 9800 GX2 is 14% faster than the GeForce GTX 260 Core 216 in general, because of its greater data rate. (explain)
Texel RateThe GeForce 9800 GX2 should be a lot (approximately 85%) faster with regards to anisotropic filtering than the GeForce GTX 260 Core 216. (explain)
Pixel RateThe GeForce 9800 GX2 will be a small bit (more or less 19%) faster with regards to full screen anti-aliasing than the GeForce GTX 260 Core 216, and also should be able to handle 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.
One or more cards in this comparison are multi-core. This means that their bandwidth, texel and pixel rates are theoretically doubled - this does not mean the card will actually perform twice as fast, but only that it should in theory be able to. Actual game benchmarks will give a more accurate idea of what it's capable of.
Memory Bandwidth: Bandwidth is the largest amount of information (counted in megabytes per second) that can be transferred over the external memory interface in a second. It is calculated by multiplying the bus width by its memory clock speed. If it uses DDR type RAM, it must be multiplied by 2 again. If DDR5, multiply by 4 instead. The higher the card's memory bandwidth, the better 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 amount of texture map elements (texels) that can be applied in one second. This figure is calculated by multiplying the total amount of texture units by the core clock speed of the chip. The higher this number, the better the graphics 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 amount of pixels the graphics card can possibly record to its local memory in one second - measured in millions of pixels per second. The number is calculated by multiplying the amount of colour ROPs 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 output rate also depends on quite a few other factors, especially the memory bandwidth - the lower the bandwidth is, the lower the ability to get to the maximum fill rate.