Dell recommends that you continue to use the Portable/Laptop power scheme to maximize battery power conservation.
Each preset power scheme has different time-out settings for putting the computer into standby mode, turning off the display, and turning off the hard drive.
Alarms Tab
HINT:
To enable audible alarms, click each Alarm Action button and select Sound alarm.
The Low battery alarm and Critical battery alarm settings alert you with a message when the battery charge falls below a certain percentage. When you
receive your computer, the Lower battery alarm and Critical battery alarm check boxes are selected. Dell recommends that you continue to use these