Cisco UCS B420 M4 Installation And Service Note page 25

Servicing the Blade Server
Step 6
Thermally bond the CPU and heat sink. Using the syringe of thermal grease provided with the replacement
CPU, apply 2 cubic centimeters of thermal grease to the top of the CPU where it will contact the heat sink.
Apply the grease in the pattern shown in the following figure, which should use approximately half the contents
of the syringe.
Figure 12: Thermal Grease Application Pattern
Step 7
Replace the heat sink. The yellow CPU heat sink install guide pins that are attached to the motherboard must
align with the cutout on the heat sink to ensure proper installation of the heat sink.
Figure 13: Replacing the Heat Sink
Cisco UCS B420 M4 Blade Server Installation and Service Note
Installing a New CPU and Heat Sink
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