Lenovo ThinkStation P720 Hardware Maintenance Manual page 185

Your computer has a special type of memory that maintains the date, time, and settings for built-in features,
such as parallel-connector assignments (configuration). A coin-cell battery keeps this information active
when you turn off the computer.
The coin-cell battery normally requires no charging or maintenance throughout its life; however, no battery
lasts forever. If the coin-cell battery fails, the date, time, and configuration information (including passwords)
are lost. An error message is displayed when you turn on the computer.
Refer to the "Lithium coin cell battery notice" in the Safety, Warranty, and Setup Guide for information about
replacing and disposing of the battery.
To remove or install the coin-cell battery, do the following:
1. Prepare your computer. See "Preparing your computer and removing the computer cover" on page 103.
2. Locate the coin-cell battery. See "Parts on the system board" on page 38.
3. Remove any parts that might impede your access to the coin-cell battery. Depending on your computer
model, you might need to remove the PCIe cards for easier access to the coin-cell battery. See "PCIe
card" on page 158 and "Full-length PCIe card" on page 164.
4. Remove the old coin-cell battery as shown.
Figure 146. Removing the coin-cell battery
5. Install a new coin-cell battery as shown.
Figure 147. Installing a coin-cell battery
6. Reinstall the PCIe cards if you have removed them. See "PCIe card" on page 158 or "Full-length PCIe
card" on page 164.
7. Reinstall the computer cover and connect the cables. See "Completing the parts replacement" on page
220.
Note: When the computer is turned on for the first time after the coin-cell battery is replaced, an error
message might be displayed. This is normal after the coin-cell battery is replaced.
8. Turn on the computer and all attached devices.
9. Use the Setup Utility program to set the date, time, and any passwords. See "Using the Setup Utility
program" on page 67.
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Chapter 9 Hardware removal and installation
179