Important. When you reinstall a logic board, you'll need to replace the thermal paste that goes between the processor on the logic board and the heat sink. Failure to remove the old paste and apply a new layer can cause the computer to overheat and sustain damage. The following steps refer to replacing the thermal paste between the processor and heat sink; follow these steps only when you are ready to place the logic board in the computer.

Use a firm plastic edge to scrape the thermal material off the raised copper heat conduit in three places. Clean the surface with rubbing alcohol.

For more advanced instructions on this procedure, see our Applying Thermal Paste Guide.