For access, remove these FRUs in order:
Attention: CPU is extremely sensitive. When you service the CPU, avoid any kind of rough handling.
Rotate the head of the screw in the direction shown by arrow  to release the lock; then remove the CPU .
Please perform the following step as shown in the picture below.
When installing: Place the CPU on the CPU socket, and then rotate the head of the screw in the direction shown by arrow a to secure the CPU.