Compare any two graphics cards:
GeForce 8600 GT 1GB DDR2 vs Radeon HD 4550 512MB
IntroThe GeForce 8600 GT 1GB DDR2 comes with a clock frequency of 540 MHz and a DDR2 memory speed of 400 MHz. It also makes use of a 128-bit memory bus, and makes use of a 80 nm design. It features 32 SPUs, 16 TAUs, and 8 Raster Operation Units.
Compare all that to the Radeon HD 4550 512MB, which comes with core clock speeds of 600 MHz on the GPU, and 800 MHz on the 512 MB of GDDR3 RAM. It features 80(16x5) SPUs along with 8 Texture Address Units and 4 Rasterization Operator Units.
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
Both cards have exactly the same bandwidth, so in theory they should perform exactly the same. (explain)
Texel RateThe GeForce 8600 GT 1GB DDR2 will be quite a bit (about 80%) faster with regards to texture filtering than the Radeon HD 4550 512MB. (explain)
Pixel RateIf running with a high resolution is important to you, then the GeForce 8600 GT 1GB DDR2 is a better choice, 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 (in units of MB per second) that can be transferred across the external memory interface in one second. It's calculated by multiplying the card's bus width by its memory clock speed. In the case of DDR type memory, the result should be multiplied by 2 once again. If it uses DDR5, multiply by ANOTHER 2x. The higher the bandwidth is, the faster the card will be in general. It especially helps with anti-aliasing, High Dynamic Range and high resolutions.
Texel Rate: Texel rate is the maximum number of texture map elements (texels) that can be applied per 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 in one second.
Pixel Rate: Pixel rate is the maximum number of pixels that the graphics card can possibly record to its local memory per second - measured in millions of pixels per second. Pixel rate is calculated by multiplying the number of colour ROPs 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 output rate also depends on quite a few other factors, especially the memory bandwidth of the card - the lower the memory bandwidth is, the lower the potential to get to the maximum fill rate.