Replacing The System Board - Lenovo IdeaCentre H520g Hardware Maintenance Manual

Replacing the system board

Attention:
Do not open your computer or attempt any repair before reading and understanding the "Important safety information"
in the User Guide. To obtain a copy of the User Guide, go to:
http://www.lenovo.com/ThinkCentreUserGuides
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 removing 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. Remove the computer cover. See "Removing the computer cover" on page 72.
3. Lay the computer on its side for easier access to the system board.
4. Remove all memory modules and PCI cards that are currently installed. See "Installing or replacing a
memory module" on page 78 and "Installing or replacing a PCI card" on page 74.
5. Carefully take note of the locations of all cable connections on the system board and disconnect all
the cables. See "Locating parts on the system board" on page 68.
6. Remove the heat sink and fan assembly from the failing system board. See "Replacing the heat sink and
fan assembly" on page 82.
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Lenovo H520gHardware Maintenance Manual