Compare any two graphics cards:
GeForce 8600 GT 256MB DDR2 vs Radeon HD 5450
IntroThe GeForce 8600 GT 256MB DDR2 features a GPU core clock speed of 540 MHz, and the 256 MB of DDR2 memory runs at 400 MHz through a 128-bit bus. It also is made up of 32 Stream Processors, 16 Texture Address Units, and 8 Raster Operation Units.
Compare those specs to the Radeon HD 5450, which features a clock frequency of 650 MHz and a DDR3 memory frequency of 800 MHz. It also features a 64-bit memory bus, and makes use of a 40 nm design. It is comprised of 80(16x5) SPUs, 8 Texture Address Units, and 4 Raster Operation Units.
(No game benchmarks for this combination yet.)
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
Both cards have the exact same bandwidth, so theoretically they should have identical performance. (explain)
Texel RateThe GeForce 8600 GT 256MB DDR2 will be a lot (more or less 66%) more effective at anisotropic filtering than the Radeon HD 5450. (explain)
Pixel RateThe GeForce 8600 GT 256MB DDR2 is much (more or less 66%) better at anti-aliasing than the Radeon HD 5450, and also should be capable of handling higher screen resolutions more effectively. (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 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 interface width by its memory speed. If the card has DDR type RAM, the result should be multiplied by 2 again. If DDR5, multiply by ANOTHER 2x. The better the card's memory bandwidth, the faster 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 number of texture map elements (texels) that are processed in one second. This figure is worked out by multiplying the total number of texture units by the core clock speed of the chip. The higher this number, the better the graphics 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 write to the local memory in one second - measured in millions of pixels per second. The figure is worked out by multiplying the number of Render Output Units by the the core clock speed. ROPs (Raster Operations Pipelines - sometimes also referred to as Render Output Units) are responsible for outputting the pixels (image) to the screen. The actual pixel output rate also depends on quite a few other factors, most notably the memory bandwidth of the card - the lower the memory bandwidth is, the lower the ability to get to the maximum fill rate.