Compare any two graphics cards:
GeForce GT 640 DDR3 vs Radeon HD 5850
IntroThe GeForce GT 640 DDR3 has core speeds of 900 MHz on the GPU, and 1782 MHz on the 2048 MB of DDR3 memory. It features 384 SPUs along with 32 TAUs and 16 ROPs.
Compare all of that to the Radeon HD 5850, which comes with GPU core speed of 725 MHz, and 1024 MB of GDDR5 memory running at 1000 MHz through a 256-bit bus. It also features 1440(288x5) Stream Processors, 72 TAUs, and 32 Raster Operation Units.
(No game benchmarks for this combination yet.)
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
Theoretically speaking, the Radeon HD 5850 should be much faster than the GeForce GT 640 DDR3 in general. (explain)
Texel RateThe Radeon HD 5850 will be a lot (about 81%) better at anisotropic filtering than the GeForce GT 640 DDR3. (explain)
Pixel RateThe Radeon HD 5850 will be a lot (approximately 61%) better at FSAA than the GeForce GT 640 DDR3, and also should be able to handle higher screen 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.
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 max amount of information (counted in MB per second) that can be transported over the external memory interface in a second. The number is calculated by multiplying the bus width by its memory speed. In the case of DDR type RAM, it must be multiplied by 2 once again. If it uses DDR5, multiply by 4 instead. The higher the memory bandwidth, the better the card will be in general. It especially helps with AA, High Dynamic Range and high resolutions.
Texel Rate: Texel rate is the maximum amount of texture map elements (texels) that can be applied in one second. This figure is worked out by multiplying the total amount of 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 applied per second.
Pixel Rate: Pixel rate is the most pixels the video card could possibly record to its local memory in one second - measured in millions of pixels per second. Pixel rate is calculated by multiplying the amount of colour ROPs by the clock 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 fill rate is also dependant 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.