8-26 System Upgrade12. Place the heat sink on the CPU and secure it with 4screws. Loosely fasten the screws in thecross-coupling way, and then fasten them tightly.13. Check that the heat sink mounted on the CPU is levelwith the motherboard.IMPORTANT: If the heat sink is leaning, remove it and then mount it again. The following arepossible causes:- The CPU has not been installed correctly.- The screws have not been fastened tight enough. Do not move the heat sink that has been secured with the screws.14. Insert the cable and fix the cooling fan unit.15. Install the CPU/IO module referring to page 8-16.16. Connect the power cord.17. Turn on the power by pressing the POWER switch.18. Verify that POST displays no error message. If an error message is displayed, write it down andcheck it in the error message list on page 7-4.Removing CPU (Model with Air-cooling Kit)Removal of a CPU (model with air-cooling kit) is the reverse of installation.
