Lenovo 7099U1U, Hardware Maintenance Manual

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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:
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. Remove the computer cover. See “Removing the computer cover” on page 71.
3. Remove the front bezel. See “Removing and reinstalling the front bezel” on page 72.
4. Lay the computer on its side for easier access to the system board.
5. Disconnect the front audio and USB assembly cables from the system board. See “Locating parts on the
system board” on page 69.
6. Remove all memory modules and PCI cards that are currently installed. See “Installing or replacing a
memory module” on page 76 and “Installing or replacing a PCI card” on page 74.
7. 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 69.
8. Remove the heat sink and fan assembly from the failing system board. See “Replacing the heat sink and
fan assembly” on page 81.
9. Remove the six screws that secure the system board.
Figure 30. Removing the six screws that secure the system board
10. Carefully slide the system board so that it can be released from the mounting studs that secure the
system board in place.
11. Lift the system board out of the chassis.
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ThinkCentre Hardware Maintenance Manual