HP DM4 - Manual (Page 47)

RTC battery
Description Spare part number
RTC battery 449137-001
Before removing the RTC battery, follow these steps:
1. Shut down the computer. If you are unsure whether the computer is off or in Hibernation, turn
the computer on, and then shut it down through the operating system.
2. Disconnect all external devices connected to the computer.
3. Disconnect the power from the computer by first unplugging the power cord from the AC outlet
and then unplugging the AC adapter from the computer.
4. Remove the battery (see Battery on page 36 ).
5. Remove the memory/wireless module compartment cover (see Memory module on page 37 )
Remove the RTC battery:
1. Release the RTC battery from the clips on the system board (1).
2. Remove the RTC battery (2).
Reverse this procedure to install the RTC battery.
Component replacement procedures 39