When you set your iMac to automatically sleep after a specified period of time, an internal counter measures the amount of time your computer has been inactive. When the counter's time matches the amount of time you specified, the computer will go to sleep and display the pulsing amber light.
Network activities listed below can continually reset the idle counter so that the computer never fully sleeps:
- Having Personal File Sharing turned on.
- Leaving a Web page open in your browser which auto-refreshes itself every few minutes.
In these cases the display will sleep but the processor will continue to be awake and the power light will remain green.
To put your iMac (Slot Loading) computer into a deep sleep state you can do either of the following:
- Turn off File Sharing and quit other applications which could keep the computer active.
- Manually put the computer to sleep, either by selecting Sleep from the Special menu or by pressing the Power button on the keyboard and clicking the Sleep button in the resulting dialog.