Nexcom Peak 555A User Manual page 29

Peak 555A User's Guide
The DIMM used SDRAM memory. Please be noted that if the 100MHz
CPU external lock is turned on, the memory should be SDRAM only and
PC-100 complied.
Capability Expanding
DIMM (Bank 1)
DIMM (Bank 0)
Figure 3-2 Memory Banks
3-2