Epson Endeavor 468C - Manual (Page 128)

4. Position the power supply cable connector so that its notched
corners line up with the notched corners of the drive’s
power supply connector, as shown below. Make sure the
holes fit over all the pins and then push in the connector.
diskette drive
notched
corners
hard disk drive
notched
Caution
If you do not align the cable connector correctly, you could
severly damage your drive when you push it in.
Installing and Removing Drives 5-25