Compare any two graphics cards:
GeForce 8500 GT vs Radeon HD 5450
IntroThe GeForce 8500 GT comes with a GPU core speed of 450 MHz, and the 512 MB of DDR2 RAM is set to run at 400 MHz through a 128-bit bus. It also features 16 SPUs, 8 Texture Address Units, and 4 Raster Operation Units.
Compare those specifications to the Radeon HD 5450, which comes with GPU clock speed of 650 MHz, and 512 MB of DDR3 RAM set to run at 800 MHz through a 64-bit bus. It also is comprised of 80(16x5) Stream Processors, 8 TAUs, and 4 ROPs.
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
Both cards have the exact same bandwidth, so theoretically they should perform the same. (explain)
Texel RateThe Radeon HD 5450 should be quite a bit (approximately 44%) more effective at AF than the GeForce 8500 GT. (explain)
Pixel RateThe Radeon HD 5450 should be quite a bit (about 44%) better at FSAA than the GeForce 8500 GT, and also will be able to handle higher resolutions without slowing down too much. (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: Bandwidth is the max amount of data (in units of megabytes per second) that can be moved across the external memory interface within a second. It's worked out by multiplying the card's interface width by its memory clock speed. In the case of DDR RAM, the result should be multiplied by 2 again. If DDR5, multiply by 4 instead. The higher the card's memory bandwidth, the better the card will be in general. It especially helps with AA, HDR and higher screen resolutions.
Texel Rate: Texel rate is the maximum amount of texture map elements (texels) that can be processed per second. This figure is calculated by multiplying the total amount of texture units by the core speed of the chip. The better this number, the better the graphics card will be at texture filtering (anisotropic filtering - AF). It is measured in millions of texels applied in one second.
Pixel Rate: Pixel rate is the maximum number of pixels that the graphics chip can possibly record to the local memory per second - measured in millions of pixels per second. The figure is worked out by multiplying the number of Raster Operations Pipelines 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 rate is also dependant on many other factors, most notably the memory bandwidth - the lower the memory bandwidth is, the lower the ability to get to the maximum fill rate.