Compare any two graphics cards:
GeForce 9800 GX2 vs Radeon HD 4870 512MB
IntroThe GeForce 9800 GX2 uses a 65 nm design. nVidia has clocked the core speed at 600 MHz. The GDDR3 memory runs at a frequency of 1000 MHz on this specific card. It features 128 SPUs as well as 64 TAUs and 16 ROPs.
Compare all of that to the Radeon HD 4870 512MB, which has a clock speed of 750 MHz and a GDDR5 memory speed of 900 MHz. It also features a 256-bit memory bus, and makes use of a 55 nm design. It is comprised of 800(160x5) SPUs, 40 Texture Address Units, and 16 ROPs.
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
The GeForce 9800 GX2 should theoretically be a small bit faster than the Radeon HD 4870 512MB overall. (explain)
Texel RateThe GeForce 9800 GX2 should be quite a bit (more or less 156%) better at AF than the Radeon HD 4870 512MB. (explain)
Pixel RateIf running with a high screen resolution is important to you, then the GeForce 9800 GX2 is the winner, 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.
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.
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 largest amount of data (measured in MB per second) that can be transported across the external memory interface within a second. It's calculated by multiplying the interface width by the speed of its memory. If the card has DDR memory, the result should be multiplied by 2 once again. If it uses DDR5, multiply by ANOTHER 2x. The higher the memory bandwidth, the better the card will be in general. It especially helps with AA, High Dynamic Range and high resolutions.
Texel Rate: Texel rate is the maximum amount of texture map elements (texels) that are processed in one second. This figure is calculated by multiplying the total amount of texture units of the card by the core 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 a second.
Pixel Rate: Pixel rate is the maximum number of pixels the graphics card can possibly write to the local memory in one second - measured in millions of pixels per second. Pixel rate is calculated by multiplying the number of Raster Operations Pipelines by the the core speed of the card. ROPs (Raster Operations Pipelines - aka 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, most notably the memory bandwidth - the lower the memory bandwidth is, the lower the potential to reach the max fill rate.