Compare any two graphics cards:
GeForce GT 240 GDDR5 vs Radeon HD 4850 X2 1GB
IntroThe GeForce GT 240 GDDR5 comes with a clock frequency of 550 MHz and a GDDR5 memory speed of 850 MHz. It also uses a 128-bit bus, and makes use of a 40 nm design. It features 96 SPUs, 32 TAUs, and 8 Raster Operation Units.
Compare those specs to the Radeon HD 4850 X2 1GB, which uses a 55 nm design. AMD has clocked the core speed at 625 MHz. The GDDR3 RAM works at a frequency of 993 MHz on this particular card. It features 800(160x5) SPUs along with 40 Texture Address Units and 16 Rasterization Operator Units.
(No game benchmarks for this combination yet.)
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
In theory, the Radeon HD 4850 X2 1GB should be 134% faster than the GeForce GT 240 GDDR5 in general, due to its greater bandwidth. (explain)
Texel RateThe Radeon HD 4850 X2 1GB should be a lot (more or less 184%) more effective at AF than the GeForce GT 240 GDDR5. (explain)
Pixel RateIf running with lots of anti-aliasing is important to you, then the Radeon HD 4850 X2 1GB is the winner, by a large margin. (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 maximum amount of information (measured in megabytes per second) that can be transported over the external memory interface in a second. It is calculated by multiplying the card's bus width by its memory speed. In the case of DDR RAM, it should be multiplied by 2 once 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, High Dynamic Range and higher screen resolutions.
Texel Rate: Texel rate is the maximum amount of texture map elements (texels) that are applied per second. This number is worked out by multiplying the total texture units 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 per second.
Pixel Rate: Pixel rate is the most pixels that the graphics card could possibly record to the local memory per second - measured in millions of pixels per second. Pixel rate is calculated by multiplying the amount of ROPs by the clock speed of the card. ROPs (Raster Operations Pipelines - also called Render Output Units) are responsible for outputting the pixels (image) to the screen. The actual pixel rate also depends on quite a few other factors, most notably the memory bandwidth of the card - the lower the bandwidth is, the lower the ability to reach the maximum fill rate.