Compare any two graphics cards:
GeForce GT 240 GDDR5 vs Radeon HD 4850 X2 1GB
IntroThe GeForce GT 240 GDDR5 features core speeds of 550 MHz on the GPU, and 850 MHz on the 512 MB of GDDR5 memory. It features 96 SPUs along with 32 TAUs and 8 Rasterization Operator Units.
Compare those specs to the Radeon HD 4850 X2 1GB, which comes with a GPU core clock speed of 625 MHz, and 1024 MB of GDDR3 memory set to run at 993 MHz through a 256-bit bus. It also features 800(160x5) SPUs, 40 Texture Address Units, and 16 Raster Operation 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 be quite a bit faster than the GeForce GT 240 GDDR5 in general. (explain)
Texel RateThe Radeon HD 4850 X2 1GB should be quite a bit (approximately 184%) better at texture filtering than the GeForce GT 240 GDDR5. (explain)
Pixel RateThe Radeon HD 4850 X2 1GB should be much (more or less 355%) more effective at anti-aliasing than the GeForce GT 240 GDDR5, and should be able to handle higher screen resolutions better. (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 data (counted in megabytes per second) that can be transported past the external memory interface within a second. The number is worked out by multiplying the bus width by the speed of its memory. In the case of DDR type memory, it should be multiplied by 2 again. If it uses DDR5, multiply by ANOTHER 2x. The better the memory bandwidth, the better 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 can be applied per second. This is worked out by multiplying the total texture units by the core 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 per second.
Pixel Rate: Pixel rate is the maximum number of pixels the video card could possibly record to its local memory per second - measured in millions of pixels per second. The figure 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 outputting the pixels (image) to the screen. The actual pixel fill rate also depends on lots of other factors, most notably the memory bandwidth of the card - the lower the memory bandwidth is, the lower the ability to get to the max fill rate.