HP Elitebook 820 G1 Getting Started page 24

Component
(2)
(3)
14 Chapter 2 Getting to know your computer
Service door release lock
Vents (2)
Description
Releases the service door from the computer.
A security screw is available to prevent the
service door from being accidentally removed.
Enable airflow to cool internal components.
NOTE: The computer fan starts up
automatically to cool internal components and
prevent overheating. It is normal for the
internal fan to cycle on and off during routine
operation.