Thermal grease

The thermal grease must be replaced whenever the heat sink has been removed from the top of the microprocessor and is going to be reused or when debris is found in the grease.

Important:

Thermal grease can be stayed on a heat sink for 2 years. Check the manufacturing date on the new heat sink and if is over 2 years, you need to remove the older grease from a heat sink and re-grease it to avoid seating issues.

When you are installing the heat sink on the same microprocessor that it was removed from, make sure that the following requirements are met:
  • The thermal grease on the heat sink and microprocessor is not contaminated.
  • Additional thermal grease is not added to the existing thermal grease on the heat sink and microprocessor.
Note:

To replace damaged or contaminated thermal grease on the microprocessor and heat sink, complete the following steps:

  1. Place the heat sink on a clean work surface.
  2. Remove the cleaning pad from its package and unfold it completely.
  3. Use the cleaning pad to wipe the thermal grease from the bottom of the heat sink.
    Note: Make sure that all of the thermal grease is removed.
  4. Use a clean area of the cleaning pad to wipe the thermal grease from the microprocessor; then, dispose of the cleaning pad after all of the thermal grease is removed.
  5. Use the thermal-grease syringe to place 9 uniformly spaced dots of 0.02 ml each on the top of the microprocessor. The outermost dots must be within approximately 5 mm of the edge of the microprocessor; this is to ensure uniform distribution of the grease.
    Figure 1. Thermal grease distribution
    Thermal grease distribution

    Note: If the grease is properly applied, approximately half of the grease will remain in the syringe.
    Figure 2. Syringe
    Syringe

  6. Install the heat sink onto the microprocessor as described in Replacing a microprocessor and heat sink.