Compare any two graphics cards:
GeForce 8600 GT 256MB DDR2 vs Radeon HD 5450
IntroThe GeForce 8600 GT 256MB DDR2 has a GPU core clock speed of 540 MHz, and the 256 MB of DDR2 RAM is set to run at 400 MHz through a 128-bit bus. It also is made up of 32 SPUs, 16 Texture Address Units, and 8 ROPs.
Compare those specifications to the Radeon HD 5450, which has clock speeds of 650 MHz on the GPU, and 800 MHz on the 512 MB of DDR3 RAM. It features 80(16x5) SPUs along with 8 TAUs and 4 Rasterization Operator Units.
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
Both cards have the exact same bandwidth, so in theory they should perform the same. (explain)
Texel RateThe GeForce 8600 GT 256MB DDR2 is a lot (approximately 66%) more effective at texture filtering than the Radeon HD 5450. (explain)
Pixel RateIf running with lots of anti-aliasing is important to you, then the GeForce 8600 GT 256MB DDR2 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.
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 transferred past the external memory interface in a second. It is calculated by multiplying the interface width by its memory speed. If it uses DDR RAM, it must be multiplied by 2 once 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, High Dynamic Range and high resolutions.
Texel Rate: Texel rate is the maximum amount of texture map elements (texels) that are 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 higher this number, the better the video card will be at handling texture filtering (anisotropic filtering - AF). It is measured in millions of texels processed in a second.
Pixel Rate: Pixel rate is the maximum amount of pixels the video card could possibly write to the local memory per second - measured in millions of pixels per second. Pixel rate is calculated by multiplying the amount of Render Output Units by the clock speed of the card. ROPs (Raster Operations Pipelines - aka Render Output Units) are responsible for filling the screen with pixels (the image). 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 potential to get to the max fill rate.