Compare any two graphics cards:
GeForce 9800 GX2 vs Radeon HD 4870 512MB
IntroThe GeForce 9800 GX2 uses a 65 nm design. nVidia has set the core speed at 600 MHz. The GDDR3 memory is set to run at a frequency of 1000 MHz on this card. It features 128 SPUs as well as 64 TAUs and 16 ROPs.
Compare those specs to the Radeon HD 4870 512MB, which features a clock frequency of 750 MHz and a GDDR5 memory speed of 900 MHz. It also uses a 256-bit bus, and makes use of a 55 nm design. It features 800(160x5) SPUs, 40 Texture Address Units, and 16 ROPs.
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
In theory, the GeForce 9800 GX2 should be a little bit faster than the Radeon HD 4870 512MB overall. (explain)
Texel RateThe GeForce 9800 GX2 is quite a bit (approximately 156%) better at texture filtering than the Radeon HD 4870 512MB. (explain)
Pixel RateIf using a high screen resolution is important to you, then the GeForce 9800 GX2 is superior to the Radeon HD 4870 512MB, and very much so. (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 information (measured in megabytes per second) that can be transferred over the external memory interface within a second. It is calculated by multiplying the interface width by its memory clock speed. If the card has DDR type RAM, it should be multiplied by 2 again. If it uses DDR5, multiply by 4 instead. The better the memory bandwidth, the faster the card will be in general. It especially helps with anti-aliasing, HDR and high resolutions.
Texel Rate: Texel rate is the maximum texture map elements (texels) that are applied per second. This is worked out by multiplying the total texture units by the core clock speed of the chip. The better the texel rate, the better the card will be at 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 video card could possibly record to the local memory in one second - measured in millions of pixels per second. Pixel rate is worked out by multiplying the amount of Raster Operations Pipelines by the the card's clock speed. 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 fill rate also depends on many other factors, especially the memory bandwidth of the card - the lower the memory bandwidth is, the lower the ability to reach the max fill rate.