Epson 3865X Plus - Manual (Page 232)

Position the power supply cable connector so that the
notched comers on the connector line up with the notched
corners of the power supply socket on your drive.
notched corners
Make sure the holes fit over all the pins and then push the
connector onto the pins.
If you do not correctly align the holes with the pins, you
could severely damage your disk drive when you push in
the connector.
If you do not need to reinstall a vertically mounted hard
disk drive, see “Replacing the Subassembly,” on page B-47.
If you just connected the power supply cable to your
vertically mounted hard disk drive, perform step 8 again to
connect the power supply cable to the drive you just
installed in the horizontal drive bay. Then see “Replacing
the Drive on the Subassembly,” on page B-42, for
instructions on reinstalling the vertically mounted hard disk
drive.
Installing and Removing Disk Drives B-41