About Automatic Processor Performance Setting
Summary
Learn what automatic processor performance is and how it can save energy and battery power.
Products Affected
PowerBook G4 (17-inch 1.5GHZ), PowerBook G4 (17-inch 1.33GHZ), PowerBook G4 (15-inch FW800), PowerBook G4 (15-inch 1.5/1.33GHZ), PowerBook G4 (12-inch DVI), PowerBook G4 (12-inch 1.33GHZ), iBook G4, Power Mac G5 (Late 2005), Power Mac G5 (Late 2004), Power Mac G5 (June 2004), Power Mac G5 (Early 2005), Power Mac G5, iMac G5 (20-Inch), iMac G5 (20-Inch iSight), iMac G5 (17-Inch iSight), iMac G5 ALS (17-Inch), iMac G5 ALS (20-Inch)
Setting your processor performance to automatic allows your computer to save energy. When you turn it on, the microprocessor's voltage, bus speed, and clock speed are adjusted to answer the current demands on the system. The advantage of this design is a longer battery life on portable computers and fewer running fans on desktop computers because of lower operating temperatures.
If you are using professional applications, games with intensive video processing, or other applications that use the microprocessor intensively, the Automatic option in Energy Saver may not provide the best microprocessor performance. If you know you are going to be placing a significant demand on the microprocessor, change your Energy Saver setting to Highest.
Selecting the Energy Setting
To set processor performance to automatic in in Mac OS X v10.2, Mac OS X v10.3, Mac OS X v10.4, and v10.5:
- From the Apple () menu, choose System Preferences.
- From the View menu, choose Energy Saver.
- Click the Options tab, then choose an option from the Processor Performance pop-up menu.
Automatic: The microprocessor will change speeds based on current demands.
Highest: The microprocessor will run at the highest speed.
Reduced: The microprocessor will run at a reduced speed.
Above: Energy Saver settings in Mac OS X v10.2.x
Above: Energy Saver settings in Mac OS X v10.3.x
Above: Energy Saver settings in Mac OS X v10.4.x and v10.5.x