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Power Saving Modes

The power manager has been redesigned to reduce power consumption in Sleep mode. The new version, Power Manager 2.0, is a native Mac OS manager designed to implement common power management policy across all Macintosh models by means of the new Power Plugin component.

Although the current public Power Manager interfaces will be maintained for application compatibility, this is a major revision that may affect developers. Information about the API changes for Power Manager 2.0 is available in a technote, which can be obtained from the web site at

http://developer.apple.com/technotes/

Here is a list of the attributes of Sleep mode on the iMac family of computers.

• The main processor is off.

• Inactive systems, such as the hard drive and the sound system, are off.

• Main memory is in self-refresh mode.

• The graphics card's oscillator is off (the AGP clock is still on).

• The clocks for the KeyLargo IC are stopped.

• USB and FireWire ports are in suspend mode (the PHY ICs are still on).

• Ethernet and modem interfaces are on only if Wake-on-LAN has been selected in the Energy Saver control panel.