Lenovo THINKCENTRE 4215 Hardware Maintenance Manual page 95

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 75.
5. Remove the secondary hard disk drive. See "Replacing the secondary hard disk drive" on page 93.
6. Remove the heat sink and fan assembly from the failing system board. See "Replacing the heat sink and
fan assembly" on page 85.
7. Remove the microprocessor from the failing system board. See "Replacing the microprocessor" on
page 86.
8. Remove the battery from the failing system board. See "Replacing the battery" on page 83.
9. Note the location of all cable connections on the system board and disconnect all cables. See "Locating
parts on the system board" on page 71.
10. Remove the eight screws that secure the system board to the chassis, following the sequence shown
in the illustration:
Figure 23. Removing the system board
11. Carefully lift the failing system board out of the chassis.
12. Position the new system board into the chassis so that the screw holes in the new system board
are aligned with those in the chassis. Install the screws that secure the system board following the
sequence shown in Removing the system boardFigure 23 on page 89.
13. Remove the microprocessor socket cover from the new system board.
14. Install the memory modules, PCI cards, battery, microprocessor, and heat sink and fan assembly that
you removed from the failing system board to the new system board.
15. Reinstall the secondary hard disk drive. See "Replacing the secondary hard disk drive" on page 93.
16. Connect all cables to the system board. See "Locating parts on the system board" on page 71.
17. Go to "Completing the FRU replacement" on page 103.
.
Chapter 9 Replacing FRUs
89