Using a Battery 41Check the Battery HealthNOTE: You can check battery health in one of two ways: by using the charge gauge on the battery as describedbelow or by using the Battery Meter in Dell QuickSet. For information about QuickSet, right-click the icon inthe taskbar, and click Help.To check the battery health using the charge gauge, press and hold the status button on the batterycharge gauge for at least 3 seconds. If no lights appear, the battery is in good condition, and more than80 percent of its original charge capacity remains. Each light represents incremental degradation. If fivelights appear, less than 60 percent of the charge capacity remains, and you should consider replacing thebattery. See "Specifications" on page 155 for more information about the battery operating time.Low-Battery WarningNOTICE: To avoid losing or corrupting data, save your work immediately after a low-battery warning, and thenconnect the computer to an electrical outlet. If the battery runs completely out of power, hibernate mode beginsautomatically.By default, a pop-up window warns you when the battery charge is approximately 90 percent depleted.You can change the settings for the battery alarms. See "Configuring Power Management Settings" onpage 43 for information about accessing QuickSet or the Power Options Properties window.Conserving Battery PowerPerform the following actions to conserve battery power:• Connect the computer to an electrical outlet when possible because battery life is largely determinedby the number of times the battery is used and recharged.• Place the computer in standby mode or hibernate mode when you leave the computer unattended forlong periods of time. See "Power Management Modes" on page 41 for more information about standbyand hibernate modes.• Use the Power Management Wizard to select options to optimize your computer’s power usage. Theseoptions can also be set to change when you press the power button, close the display, or press. See "Configuring Power Management Settings" on page 43 for more information onusing the Power Management Wizard.NOTE: See "Battery Performance" on page 39 for more information on conserving battery power.Power Management ModesStandby ModeStandby mode conserves power by turning off the display and the hard drive after a predeterminedperiod of inactivity (a time-out). When the computer exits standby mode, it returns to the sameoperating state it was in before entering standby mode.NOTICE: If your computer loses AC and battery power while in standby mode, it may lose data.