Compaq Presario 3000 - Desktop PC Maintenance And Service Manual page 108

Removal and Replacement Procedures
2. Remove the RTC battery from the socket on the system board
(Figure 5-29).
✎
The notebook uses a BR1225 disk cell battery. The RTC battery
should be installed with the "+" facing up.
Figure 5-29. Removing the RTC Battery
Reverse the preceding procedure to install the RTC battery.
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