Toshiba PPM78U05L01E User Manual

Page of 258
User’s Manual
6-9
PORTÉGÉ M780
Maximizing battery operating time
A battery’s usefulness depends on how long it can supply power on a 
single charge, while how long the charge lasts in a battery depends on:
Processor speed
Screen brightness
System Sleep Mode
System Hibernation Mode
Display power off period
Hard disk drive power off period
How often and for how long you use the hard disk drive and external 
disk(c) drives, for example, optical disc and floppy diskette drive.
How much charge the battery contained to begin with.
How you use optional devices, such as a PC Cards, to which the 
battery supplies power.
Whether you enable Sleep Mode, which can conserve battery power if 
you are frequently turning the computer off and on.
Where you store your programs and data.
Whether you close the display panel when you are not using the 
keyboard - closing the display saves power.
The environmental temperature - operating time decreases at low 
temperatures.
The condition of the battery terminals - you should always ensure the 
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:
Retention time
Battery type
State and Retention Time
Battery pack 
(51Wh, 6 Cell)
about 4 days (Sleep Mode)
about 40 days (Boot Mode)
Slice Expansion Battery
(44Wh, 6 Cell)
about 3 days (Sleep Mode)
about 35 days (Boot Mode)
RTC battery
30 days