HP ProLiant DL60 Gen9 User Manual page 60

Finish the installation by completely tightening the screws in the same sequence.
b.
To determine which fan blanks need to be removed to install the additional fans, see "Fan population
guidelines."
Remove the air baffle (on page 19).
1.
Remove the fan blanks.
2.
Install the additional fans included in the processor option kit.
3.
Hardware options installation 60