Asus Q502L E-Manual page 21

Volume button
This button turns the volume up or down on your Notebook PC.
Power button
Press the power button to turn your Notebook PC on or off.
You can also use the power button to put your Notebook PC to
sleep or hibernate mode and wake it up from sleep or hibernate
mode.
In the event that your Notebook PC becomes unresponsive,
press and hold the power button for about four (4) seconds
until your Notebook PC shuts down.
Notebook PC E-Manual
21