Toshiba Satellite Pro U400 - Manual (Page 107)

User’s Manual 6-9
Power and Power-Up Modes
Maximizing battery operating time
A battery’s usefulness depends on how long it can supply power on a
single charge.
How long the charge lasts in a battery depends on:
■ CPU processing speed (Depends on the model you purchased)
■ Screen brightness
■ Cooling method (Depends on the model you purchased)
■ System Sleep Mode
■ System Hibernation
■ Monitor power off
■ How often and how long you use the hard disk, optical disc.
■ How much charge the battery contained to begin with.
■ How you use optional devices, such as a PC Card, to which the battery
supplies power.
■ Enabling Sleep Mode conserves battery power if you are frequently
turning the computer off and on.
■ Where you store your programs and data.
■ Closing the display when you are not using the keyboard saves power.
■ Operating time decreases at low temperatures.
■ The condition of the battery terminals. Make sure the battery terminals
stay clean by wiping them with a clean dry cloth before installing the
battery pack.
Retaining data with power off
When you turn off your computer with fully charged batteries, the batteries
retain data for the following approximate time periods.
Extending battery life
To maximize the life of your battery pack:
■ At least once a month, disconnect the computer from a power source
and operate it on battery power until the battery pack fully discharges.
Before doing so, follow the steps below.
1. Turn off the computer's power.
2. Disconnect the AC adaptor and turn on the computer's power. If it does
not turn on go to step 4.
Battery pack
(3cell, 6cell, 9cell)
Approximately 1.5 days (Sleep mode, 3-cell)
Approximately 3 days (Sleep mode, 6-cell)
Approximately 5 days (Sleep mode, 9-cell)
Approximately 1 month (Shut down mode, All
type of battery packs)
RTC battery Approximately 1 month