Apple Xserve Intel (Late 2006) DIY Procedure for Heatsink - Manual (Page 7)

Xserve (Late 2006) Processor Heat Sink Replacement Instructions 
Clean off any existing thermal grease on the top face of the processor using the alcohol wipe
provided with the replacement part, being careful not to get any thermal grease on the
processor contacts.
Apply the contents on a single syringe of thermal grease (approximately 4.5 cc) to the top
surface of the processor.
Important: Be sure not to get any grease anywhere on the processor other than the very
top, flat surface that directly contacts the heat sink.
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