Lenovo ThinkCentre A70z ALL-IN-ONE, Hardware Maintenance Manual

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a. Partially install screw 1 , fully install screw 3 , and then fully install screw 1 .
b. Partially install screw 2 , fully install screw 4 , and then fully install screw 2 .
7. Close the system board shielding. See “Closing the system board shielding” on page 72.
8. Go to “Completing the FRU installation” on page 108.
Replacing the system board
This section provides instructions on how to replace the system board.
CAUTION:
The microprocessor and heat sink assembly might be very hot. Turn off the computer
and wait three to five minutes to let the computer cool before opening the computer cover.
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
Removing the system board
To remove the system board, do the following:
1. Turn off the computer.
2. Disconnect all cables, power cords, and external options from your computer. See “Rear connectors”
on page 65.
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ThinkCentre Hardware Maintenance Manual