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 processor.

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