Compare any two graphics cards:
GeForce GT 240 GDDR5 vs Radeon HD 4850 X2 1GB
IntroThe GeForce GT 240 GDDR5 has a GPU clock speed of 550 MHz, and the 512 MB of GDDR5 RAM is set to run at 850 MHz through a 128-bit bus. It also is made up of 96 Stream Processors, 32 TAUs, and 8 ROPs.
Compare all of that to the Radeon HD 4850 X2 1GB, which comes with core clock speeds of 625 MHz on the GPU, and 993 MHz on the 1024 MB of GDDR3 memory. It features 800(160x5) SPUs along with 40 TAUs and 16 Rasterization Operator Units.
(No game benchmarks for this combination yet.)
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
The Radeon HD 4850 X2 1GB, in theory, should perform quite a bit faster than the GeForce GT 240 GDDR5 overall. (explain)
Texel RateThe Radeon HD 4850 X2 1GB should be quite a bit (more or less 184%) more effective at anisotropic filtering than the GeForce GT 240 GDDR5. (explain)
Pixel RateThe Radeon HD 4850 X2 1GB should be much (about 355%) better at anti-aliasing than the GeForce GT 240 GDDR5, and should be able to handle higher resolutions without losing too much performance. (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 maximum amount of information (counted in megabytes 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 its memory speed. If the card has DDR RAM, it should be multiplied by 2 once again. If DDR5, multiply by 4 instead. The better the card's 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 can be applied in one second. This number is calculated by multiplying the total number of texture units by the core clock speed of the chip. The higher the texel rate, the better the video 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 number of pixels that the graphics card can possibly record to its local memory in one second - measured in millions of pixels per second. Pixel rate is worked out by multiplying the amount of ROPs 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 rate also depends on lots of other factors, most notably the memory bandwidth - the lower the bandwidth is, the lower the potential to get to the max fill rate.