Samsung M55 - Manual (Page 103)

5-3 Chapter 5. System Management
Using the Power button
You can configure the function of the power button.
Click Start > Control Panel > Performance and Maintenance >
Power Options and select the Advanced tab.
Configure the Power button function.
Configuring the function of the < fn >+< >
key combination.
CC CC aa aa uu uu tt tt ii ii oo oo nn nn
When the Power button is configured to put the system into Power-Saving Mode,
manually shutting down the computer requires the Power button to be pressed and
held for more than 4 seconds.