Compare any two graphics cards:
GeForce 8600 GT 512MB DDR2 vs Radeon HD 4770
IntroThe GeForce 8600 GT 512MB DDR2 has clock speeds of 540 MHz on the GPU, and 400 MHz on the 512 MB of DDR2 memory. It features 32 SPUs along with 16 Texture Address Units and 8 Rasterization Operator Units.
Compare all of that to the Radeon HD 4770, which uses a 40 nm design. AMD has set the core frequency at 750 MHz. The GDDR5 RAM is set to run at a frequency of 800 MHz on this particular card. It features 640(128x5) SPUs along with 32 Texture Address Units and 16 Rasterization Operator Units.
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
In theory, the Radeon HD 4770 is 300% quicker than the GeForce 8600 GT 512MB DDR2 overall, because of its greater data rate. (explain)
Texel RateThe Radeon HD 4770 is much (about 178%) more effective at anisotropic filtering than the GeForce 8600 GT 512MB DDR2. (explain)
Pixel RateIf using high levels of AA is important to you, then the Radeon HD 4770 is superior to the GeForce 8600 GT 512MB DDR2, 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: Bandwidth is the max amount of data (measured in MB per second) that can be transferred past the external memory interface in a second. The number is worked out by multiplying the card's interface width by its memory speed. In the case of DDR memory, it should be multiplied by 2 once again. If DDR5, multiply by 4 instead. The better the card's memory bandwidth, the better the card will be in general. It especially helps with AA, HDR and high resolutions.
Texel Rate: Texel rate is the maximum texture map elements (texels) that are applied in one second. This is calculated by multiplying the total amount of texture units by the core speed of the chip. The better this number, the better the 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 amount of pixels the graphics card can possibly record to the local memory per second - measured in millions of pixels per second. Pixel rate is calculated by multiplying the number of Render Output Units by the clock speed of the card. ROPs (Raster Operations Pipelines - also sometimes called Render Output Units) are responsible for filling the screen with pixels (the image). The actual pixel fill rate also depends on many other factors, most notably the memory bandwidth of the card - the lower the bandwidth is, the lower the ability to reach the max fill rate.