Compare any two graphics cards:
GeForce 8600 GT 512MB DDR2 vs Radeon HD 5450
IntroThe GeForce 8600 GT 512MB DDR2 features core speeds of 540 MHz on the GPU, and 400 MHz on the 512 MB of DDR2 RAM. It features 32 SPUs along with 16 TAUs and 8 ROPs.
Compare all that to the Radeon HD 5450, which comes with a clock speed of 650 MHz and a DDR3 memory speed of 800 MHz. It also uses a 64-bit bus, and makes use of a 40 nm design. It is comprised of 80(16x5) SPUs, 8 TAUs, and 4 Raster Operation Units.
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
Both cards have the exact same memory bandwidth, so theoretically they should perform exactly the same. (explain)
Texel RateThe GeForce 8600 GT 512MB DDR2 will be much (approximately 66%) better at anisotropic filtering than the Radeon HD 5450. (explain)
Pixel RateIf using high levels of AA is important to you, then the GeForce 8600 GT 512MB DDR2 is the winner, by far. (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 (in units of megabytes per second) that can be transferred past the external memory interface in a second. It's worked out by multiplying the card's interface width by its memory clock speed. In the case of DDR RAM, it must be multiplied by 2 again. If DDR5, multiply by ANOTHER 2x. The better the memory bandwidth, the faster the card will be in general. It especially helps with AA, High Dynamic Range and high resolutions.
Texel Rate: Texel rate is the maximum number of texture map elements (texels) that can be applied in one second. This number is worked out by multiplying the total number of texture units by the core speed of the chip. The better the texel rate, the better the video card will be at texture filtering (anisotropic filtering - AF). It is measured in millions of texels applied in a second.
Pixel Rate: Pixel rate is the maximum amount of pixels that the graphics card can possibly record to its local memory in a second - measured in millions of pixels per second. Pixel rate is calculated by multiplying the amount of Render Output Units by the the card's clock speed. ROPs (Raster Operations Pipelines - sometimes also referred to as Render Output Units) are responsible for filling the screen with pixels (the image). The actual pixel fill rate is also dependant on lots of other factors, especially the memory bandwidth - the lower the bandwidth is, the lower the ability to get to the maximum fill rate.