The Performa 550 is Energy Star compliant, which turns off the
screen after a few minutes. For example, if you choose 15 minutes, the
screen will darken after the computer has been inactive for 15 minutes.
Workaround: Turn off the energy saving features by:
* Choosing the Control Panels from the Apple Menu.
* Open the Screen control panel.
* Turn off the Screen Power Saver.
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