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Mobile Computing
Charging batteries
TECHNICAL NOTE: The recharging of the battery may
not occur when your computer is using all of the power
provided by the AC adaptor to run applications, features,
and devices. Your computer's Power Options utility can
be used to select a power level setting that reduces the
power required for system operation and will allow the
battery to recharge.
The battery may not start charging immediately under the
following conditions:
❖The battery is extremely hot or cold.
To ensure that the battery charges to its full capacity,
wait until it reaches room temperature (50 to 80 degrees
Fahrenheit, 10 to 26 degrees Celsius).
❖The battery is almost completely discharged.
Leave the power connected and the battery should
begin charging after a few minutes.
HINT: Once the battery is fully charged, we recommend
that you periodically operate your computer on battery
power until the battery discharges completely.
Please make a complete back up of your data to external
media before discharging the battery. For more
information, see “Backing up your work” on page 84
Charging the RTC battery
Your computer has an internal real-time clock (RTC) battery.
The RTC battery powers the System Time Clock and BIOS
memory used to store your computer’s configuration
settings. When fully charged, it maintains this information for
up to a month when the computer is powered off.
The RTC battery may have become completely discharged
while your computer was shipped, resulting in a CMOS error
message during startup. The error message may vary by
computer model.