Epson 386SX - Manual (Page 160)

2. Remove the SIMM card from its slot on the main system
board by pulling it straight up, as shown below. Then set it
on a soft surface with the components facing up.
3. Change the setting of jumper J5 as necessary. (See
“Changing the main system board jumper settings” below.)
Avoid disturbing the cable connection next to the jumper.
4. To replace the SIMM card, reinstall the card in the SIMM
card slot on the main system board and secure it to the
inside of the computer with the retaining screw.
5-18 Installing Options