HP EliteBook 8540w Mobile Workstation - Manual (Page 22)

Bottom components
Component Description
(1) SIM slot Contains a wireless subscriber identity module (SIM) (select
models only). The SIM slot is located inside the battery bay.
(2) Battery bay Holds the battery.
(3) Docking connector Connects an optional docking device.
(4) Vents (6) 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.
(5) Accessory battery connector Connects an optional accessory battery.
(6) Memory module compartment Contains two expansion memory module slots.
(7) Hard drive bay Holds the hard drive.
(8) Bluetooth compartment Contains a Bluetooth device.
(9) Wireless module compartment Contains an HP Mobile Broadband Module.
NOTE: 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 technical support through
Help and Support.
(10) Battery release latch Releases the battery from the battery bay.
10 Chapter 1 Features