Lenovo ThinkStation P520 Hardware Maintenance Manual page 207

• "Coin-cell battery" on page 170
• "Front panel I/O cage" on page 193
4. Record the cable routing and cable connections and then disconnect all cables from the system board.
See "Parts on the system board" on page 42.
5. Remove the 11 screws that secure the system board in the sequence shown in the following illustration.
Figure 177. Removing the 11 screws that secure the system board
6. Slide the system board to the front of the computer and then carefully lift the system board out of the
chassis.
7. Remove the microprocessor from the failing system board and install it on the new system board. See
"Microprocessor" on page 194.
.
Chapter 9 Hardware removal and installation
199