Epson EQUITY 386SX/16 PLUS - Manual (Page 119)

3. Position power supply connector P4 so the large tab on
the connector faces the right side of the computer.
Beginning with the six pins toward the back of the
computer, carefully line up the holes in the connector
with the pins in the socket and then push in the
connector.
Caution
If you do not correctly align the holes with the pins in
the socket, you could severely damage your computer
when you push in the connector.
4. Connect power supply connector P5 to the remaining six
pins in the socket using the same procedure.
Installing and Removing Options 5-35