User's Manual

5.2.4 Low-Battery Warning
After a low-battery warning, save your work immediately,
then connect your notebook to an electrical outlet. Hibernate
mode will begin automatically if the battery runs completely
out of power.
You will hear the low-battery warning when the battery charge is
approximately 90 percent depleted. Your notebook will beep
once, indicating approximately 10 to 15 minutes of battery
operating time remain. If you do not connect your notebook to
alternative power source during that time, there will be a periodic
beep. Your notebook will automatically enter hibernate mode if
the battery charge reaches a critically low level. For more
information, see Power Management.