9. Install the air baffle in the microprocessor tray.10. Install the microprocessor tray in the server:a. Make sure that the microprocessor-tray release latch is open; then, pushthe microprocessor tray into the server.b. Close the tray levers and make sure they are securely latched.c. Close the microprocessor-tray release latch.d. Reinstall the fans and memory cards in the server.11. Reinstall the top cover and bezel.12. Reconnect external cables and power cords.Thermal greaseThe thermal grease must be replaced whenever the heat sink has been removedfrom the top of the microprocessor and is going to be reused or when debris isfound in the grease.To replace damaged or contaminated thermal grease on the microprocessor andheat 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 heatsink.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 themicroprocessor; then, dispose of the cleaning pad after all of the thermal greaseis removed.Microprocessor 0.01 mL ofthermal grease5. Use the thermal-grease syringe to place 16 uniformly spaced dots of 0.01 mLeach on the top of the microprocessor.Note: 0.01mL is one tick mark on the syringe. If the grease is properly applied,approximately half (0.22 mL) of the grease will remain in the syringe.6. Install the heat sink onto the microprocessor as described in “Removing andinstalling a microprocessor” on page 55.58 IBM System x3850 Type 8864: Problem Determination and Service Guide