Epson EQUITY 386SX/16 PLUS - Manual (Page 156)

Pick up the hard disk drive cable and notice the
connector on the end of the cable. There is a tab on one
side of the connector, as shown below.
tab
Pull the cable over toward the socket and fold it to align
the connector with the socket. Make sure the side of the
connector with the tab lines up with the side of the
socket with the notch. Then line up the holes over all of
the pins and push in the connector.
Caution
If you do not correctly align the holes with the pins,
you could severely damage your computer when you
push in the connector.
B - 2 2 Installing and Removing Disk Drives