Epson User Manual page 118

Make sure the holes in the cable connector fit over all the
4.
pins; then push in the connector.
If you do not correctly align the holes with the pins, you
5. Locate one of the power supply cables that lead from the
power supply. (They have multi-colored wires and a plastic
connector on the end.)
6. Align the notched corners of the power supply cable
connector with the notched corners of the drive's power
connector (such as the one shown below). Make sure the
holes fit over all the pins and then push in the connector.
5-20
Installing and Removing Slimline Drives
notched corners