Compare any two graphics cards:
GeForce 9800 GX2 vs Radeon HD 4870 2GB
IntroThe GeForce 9800 GX2 makes use of a 65 nm design. nVidia has set the core frequency at 600 MHz. The GDDR3 RAM is set to run at a frequency of 1000 MHz on this card. It features 128 SPUs along with 64 Texture Address Units and 16 ROPs.
Compare those specs to the Radeon HD 4870 2GB, which uses a 55 nm design. AMD has clocked the core speed at 750 MHz. The GDDR5 RAM runs at a frequency of 900 MHz on this specific model. It features 800(160x5) SPUs along with 40 Texture Address Units and 16 Rasterization Operator Units.
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
The GeForce 9800 GX2 should theoretically be just a bit faster than the Radeon HD 4870 2GB overall. (explain)
Texel RateThe GeForce 9800 GX2 should be a lot (about 156%) faster with regards to texture filtering than the Radeon HD 4870 2GB. (explain)
Pixel RateIf running with a high resolution is important to you, then the GeForce 9800 GX2 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.
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: Memory bandwidth is the maximum amount of data (in units of MB per second) that can be moved across the external memory interface in a second. It's calculated by multiplying the card's bus width by the speed of its memory. If it uses DDR type memory, the result should be multiplied by 2 once again. If it uses DDR5, multiply by 4 instead. The better the bandwidth is, 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 texture map elements (texels) that are processed in one second. This is calculated by multiplying the total number of texture units by the core speed of the chip. The higher the texel rate, the better the 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 number of pixels that the graphics card can possibly record to the local memory in a second - measured in millions of pixels per second. The number is calculated by multiplying the number of ROPs by the the card's 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 fill rate is also dependant on lots of other factors, most notably the memory bandwidth of the card - the lower the memory bandwidth is, the lower the ability to reach the max fill rate.