Compare any two graphics cards:
GeForce 9800 GTX+ vs Radeon HD 4850 X2 512MB
IntroThe GeForce 9800 GTX+ comes with a core clock speed of 738 MHz and a GDDR3 memory speed of 1100 MHz. It also features a 256-bit bus, and makes use of a 55 nm design. It is comprised of 128 SPUs, 64 TAUs, and 16 Raster Operation Units.
Compare all that to the Radeon HD 4850 X2 512MB, which comes with core clock speeds of 625 MHz on the GPU, and 993 MHz on the 512 MB of GDDR3 RAM. It features 800(160x5) SPUs along with 40 TAUs and 16 ROPs.
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
As far as performance goes, the Radeon HD 4850 X2 512MB should theoretically be a lot better than the GeForce 9800 GTX+ in general. (explain)
Texel RateThe Radeon HD 4850 X2 512MB is a little bit (about 6%) faster with regards to AF than the GeForce 9800 GTX+. (explain)
Pixel RateThe Radeon HD 4850 X2 512MB is quite a bit (more or less 69%) faster with regards to full screen anti-aliasing than the GeForce 9800 GTX+, and also should be capable of handling higher 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.
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: Bandwidth is the largest amount of information (measured in MB per second) that can be transported past the external memory interface in one second. The number is worked out by multiplying the card's interface width by the speed of its memory. In the case of DDR type memory, it must be multiplied by 2 again. If it uses DDR5, multiply by ANOTHER 2x. The better the bandwidth is, the faster the card will be in general. It especially helps with AA, HDR and high resolutions.
Texel Rate: Texel rate is the maximum number of texture map elements (texels) that are processed per second. This figure is worked out by multiplying the total number of texture units of the card by the core clock speed of the chip. The better this number, the better the video card will be at handling texture filtering (anisotropic filtering - AF). It is measured in millions of texels applied in a second.
Pixel Rate: Pixel rate is the maximum number of pixels the video card could possibly record to its local memory in a second - measured in millions of pixels per second. Pixel rate is worked out by multiplying the amount of Render Output Units by the the card's clock speed. ROPs (Raster Operations Pipelines - also sometimes called Render Output Units) are responsible for outputting the pixels (image) to the screen. The actual pixel fill rate also depends on quite a few 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.