HP ProLiant SL250s Gen8 User Manual page 52

Remove the PCI cage.
6.
Install the controller card into the PCI cage
7.
Connect the mini-SAS cable included in this kit to the controller card.
8.
Install the PCI cage in the server.
9.
Install the bracket.
10.
Install the front GPU.
11.
Install the HDD cage.
12.
Hardware options installation 52