HP ProBook 4720s Notebook-PC - Manual (Page 75)

8 Memory modules
The computer has one memory module compartment, which is located under the keyboard. The memory
capacity of the computer can be upgraded by adding a memory module to the vacant expansion memory
module slot or by upgrading the existing memory module in the primary memory module slot.
All memory modules installed in the computer must be the same type. When upgrading memory
capacity, verify that the upgrade modules are the same as those already installed in the computer.
WARNING! To reduce the risk of electric shock and damage to the equipment, unplug the power cord
and remove all batteries before installing a memory module.
CAUTION: Electrostatic discharge (ESD) can damage electronic components. Before beginning any
procedure, touch a grounded metal object to be sure that you are discharged of static electricity.
NOTE: To use a dual-channel configuration when adding a second memory module, be sure that both
memory modules are the same size and type.
Adding or replacing memory modules
To add or replace a memory module:
1. Save your work.
2. Shut down the computer and close the display.
If you are not sure whether the computer is off or in Hibernation, turn the computer on by briefly
pressing the power button. Then, shut down the computer through the operating system.
3. Disconnect all external devices connected to the computer.
4. Unplug the power cord.
5. Turn the computer upside down on a flat surface, with the battery bay toward you.
6. Remove the battery from the computer.
Adding or replacing memory modules 65