Epson EL 3S/33 - Manual (Page 48)

Installing Memory Modules (SlMMs)
Your computer comes with 2MB or 4MB on SIMMs. By
installing additional memory modules, you
can
increase the
amount of memory in your computer up to 16MB.
There are eight SIMM sockets on the main system board, and
each can contain one memory module. You can install 256KB,
1MB, and 4MB SIMMs.
The following table shows the possible SIMM configurations;
do not install memory in any other configuration. The label on
the system board for each SIMM socket (RAM1 through RAM8)
identifies the bank of sockets where you should install SIMMs.
SlMM configurations
Installing and Removing Options 3-9