Replacing The Coin-Cell Battery - Lenovo ThinkCentre M800 User Manual

7. Lift the failing heat sink and fan assembly off the system board.
Notes:
• You might have to gently twist the heat sink and fan assembly to free it from the microprocessor.
• Do not touch the thermal grease while handling the heat sink and fan assembly.
8. Position the new heat sink and fan assembly on the system board so that the four screws are aligned
with the holes in the system board. Ensure that the heat sink and fan assembly cable faces toward the
microprocessor fan connector on the system board.
9. Follow the following sequence to install the four screws to secure the new heat sink and fan assembly.
Do not over-tighten the screws.
a. Partially tighten screw
b. Partially tighten screw
10. Connect the cable of the new heat sink and fan assembly to the microprocessor fan connector on the
system board. See "Parts on the system board" on page 6.
11. Position the heat sink fan duct on the top of the new heat sink and fan assembly as shown. Then, press
the heat sink fan duct straight down until it snaps into position.
Figure 54. Installing the heat sink fan duct
What to do next:
• To work with another piece of hardware, go to the appropriate section.
• To complete the installation or replacement, go to "Completing the parts replacement" on page 81.

Replacing the coin-cell battery

Attention: Do not open your computer or attempt any repair before reading and understanding the "Read
this first: Important safety information" on page iii.
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 coin-cell
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.
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ThinkCentre M800 and M900 User Guide
1 , then fully tighten screw
3 , then fully tighten screw
2 , and then fully tighten screw
4 , and then fully tighten screw
1 .
3 .