Dell Dimension 4550 - Manual (Page 99)

Adding Parts 99
"cable select" (see the documentation that came with the drive for
information).
14 Close the computer cover (see page 104).
NOTICE: To connect a network cable, first plug the cable into the network
wall jack and then plug it into the computer.
15 Connect your computer and devices to electrical outlets, and turn
them on.
16 See the documentation that came with the drive for instructions on
installing any software required for drive operation.
power cable
first hard-drive
cable (primary
boot drive)
second hard-drive
cable (secondary
drive)