Mobile Computing

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Charging batteries
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 operate your computer on battery power until the battery discharges completely. Doing this extends battery life and helps ensure accurate monitoring of battery capacity.

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 the following error message during startup:

BAD RTC BATTERY

BAD CHECKSUM (CMOS)

CHECK SYSTEM

NOTE

The above error message may vary by computer model.

 

The RTC battery does not charge while the computer is turned

 

off even when the AC adapter is charging the computer. The

 

RTC battery charges when the computer is powered on.

 

 

If the RTC battery is low, the real-time clock and calendar may display the incorrect time and date, or stop working.

To recharge the RTC battery, plug the computer into a live electrical outlet and leave the computer powered on for 24 hours.