HP Compaq Pro 4300 All-in-One Hardware Reference Manual page 21

NOTE:
The lifetime of the lithium battery can be extended by plugging the computer into a live AC
wall socket. The lithium battery is only used when the computer is NOT connected to AC power.
HP encourages customers to recycle used electronic hardware, HP original print cartridges, and
rechargeable batteries. For more information about recycling programs, go to
recycle.
1.
Remove all removable media, such as compact discs or USB flash drives, from the computer.
2.
Turn off the computer properly through the operating system, then turn off any external devices.
3. Disconnect the power cord from the power outlet and disconnect any external devices.
CAUTION:
You must disconnect the power cord and wait approximately 30 seconds for the
power to drain before adding or removing memory modules. Regardless of the power-on state,
voltage is always supplied to the memory modules as long as the computer is plugged into an
active AC outlet. Adding or removing memory modules while voltage is present may cause
irreparable damage to the memory modules or system board.
4. Remove/disengage any security devices that prohibit opening the computer.
5. Place the computer face down on a soft flat surface. HP recommends that you set down a blanket,
towel, or other soft cloth to protect the screen surface from scratches or other damage.
6. Remove the center access panel by pulling outward on the panel at the slot on the top edge of the
panel.
Figure 2-12 Removing the Center Access Panel
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Replacing the Battery
15