Lenovo ThinkCentre M76, Hardware Maintenance Manual, Page: 152 / 214

13. Reconnect all cables that were disconnected from the system board.
14. To complete the installation or replacement, go to “Completing the parts replacement” on page 157.
Replacing the system board
Attention:
Do not open your computer or attempt any repair before reading and understanding the “Important safety information”
in the
ThinkCentre Safety and Warranty Guide that came with your computer. To obtain a copy of the ThinkCentre
Safety and Warranty Guide , go to:
http://www.lenovo.com/support
This section provides instructions on how to replace the system board.
CAUTION:
The heat sink and microprocessor might be very hot. Turn off the computer and wait three to five
minutes to let the computer cool before opening the computer cover.
To replace the system board, do the following:
1. Remove all media from the drives and turn off all attached devices and the computer. Then, disconnect
all power cords from electrical outlets and disconnect all cables that are connected to the computer.
2. Open the computer cover. See “Opening the computer cover” on page 119.
3. Remove the front bezel. See “Removing and reinstalling the front bezel” on page 120.
4. Remove the hard disk drive. See “Replacing the hard disk drive” on page 132.
5. Pivot the optical drive bay assembly upward to gain access to the system board. See “Accessing the
system board components and drives” on page 122.
6. Remove all memory modules and PCI cards that are currently installed. See “Installing or replacing a
memory module” on page 123 and “Installing or replacing a PCI card” on page 124.
7. Remove the heat sink and fan assembly from the failing system board. See “Replacing the heat sink and
fan assembly” on page 137.
8. Carefully take note of the location of all cable connections on the system board and disconnect all the
cables. See “Locating parts on the system board” on page 117.
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ThinkCentre Hardware Maintenance Manual