Samsung ML--6100 - Manual (Page 85)

6. 2 Printer Options
Memory SIMM
The ML-6100 comes with 12 MB. You can install less on more than 12 MB
of printer memory by changing memory SIMM (single inline memory
modules).
Note: PostScript requires 12 MB of printer memory.
Review the precautions on page 6.1 and then follow this procedure
to install SIMM in your printer.
1. Turn the printer power off and disconnect the power cord.
2. Remove the control board cover.