HP ProBook 4446s Notebook-PC - Manual (Page 27)

Component Description
(3) Service door Protects the hard drive bay, the wireless LAN (WLAN)
module slot, and the memory module slots.
CAUTION: To prevent an unresponsive system, replace
the wireless module only with a wireless module
authorized for use in the computer by the governmental
agency that regulates wireless devices in your country or
region. If you replace the module and then receive a
warning message, remove the module to restore computer
functionality, and then contact support through Help and
Support. From the Start screen, type help, and then
select Help and Support.
(4) Vents (2) 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.
Identifying the bottom parts of the computer
NOTE: The service door has been removed in the following illustration.
Component Description
(1) Memory modules
Identifying the bottom parts of the computer 17