How does the USB come into effect

I see how the Magsafe and MiniDisplay works, but the USP doesn't seem to make sense. If you connect to any computer all you need is the Mini DisplayPort connecter. Why the USB?

QA Apple 27-inch LED Cinema Display

QA Apple 27-inch LED Cinema Display

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2 Answers from the Community

  • Answer

    There are three USB ports on the back of this display. Connecting the USB cable to a computer means that those three USB ports are also connected to the computer. In a sense, the display acts as a USB hub—since you give up one USB port on the actual computer, but gain three on the back of the display (for a net gain of two).

  • On a Mac the USB is used for:

    iSight Camera
    Ambient Light Sensor
    Pass Audio (in some circumstances^)
    Adjust Display Brightness

    ^MiniDisplay Port can also pass audio but not all Macs with MDP have this capability.

    Thanks ... Ken