HP 421 Notebook-PC - Manual (Page 17)

Component Description
(2) Internal display switch Turns off the display if the panel lid is closed while the power is
on.
(3) Power button ● When the computer is off, press the button to turn on the
computer.
● When the computer is on, press the button to shut down the
computer.
● When the computer is in the Sleep state, press the button
briefly to exit Sleep.
● When the computer is in Hibernation, press the button
briefly to exit Hibernation.
If the computer has stopped responding and Windows shutdown
procedures are ineffective, press and hold the power button for at
least 5 seconds to turn off the computer.
To learn more about your power settings, select Start > Control
Panel > System and Maintenance > Power Options.
Identifying hardware 5