HP Xw8400 - Workstation - 4 GB RAM Technical Reference Manual page 104

2. Remove the four processor screws slowly, being sure to loosen all the screws evenly. Loosen one
pair of diagonally opposite screws (1) until the screw shanks disengage from the system board,
and then loosen the remaining pair (2). Do not fully loosen one screw, then move on to the next.
Loosen all of the screws a little at a time, so that the processor remains level.
Figure 4-62
3. Disconnect the CPU heatsink fan connector (1) from the system board.
4. Before lifting the heatsink, carefully break the thermal compound between the CPU heatsink and
processor by rotating the heatsink back and forth (2).
Figure 4-63
5. Use alcohol and a soft cloth to clean all of the thermal interface material residue from the CPU
heatsink and processor.
CAUTION:
94 Chapter 4 Removal and replacement procedures
Identifying proper screw removal order
Removing the CPU heatsink from the system board
Allow the alcohol on the processor and CPU heatsink to dry completely.
ENWW