2 (You may install 1 or 2 pcs, however they must be of the same size.)
non-removable base memory
Prior to the Y2K upgrade, use of 3rd party flash memory required BOOT-2500= bios. This may be obtained from Cisco for free. If your router does not recognize the flash upgrade, you may need this. To upgrade the main memory, please 2502 (main memory) section.