Epson EQUITY 386SX/16 PLUS - Manual (Page 182)

3. Reach under the subassembly and grasp the two main
system board power supply cables, labeled P4 and P5.
Each connector has six pin holes and a large tab on one
side, as shown below.
There is one 12-pin power supply socket on the right side
of the main system board (toward the back) that holds
both of the power supply connectors, as shown below.
power supply
B - 4 8
Installing and Removing Disk Drives