OK, this is interesting. I just replaced a 128 meg chip or a 256, giving my a total of 512. When I closed up my Lombard 333MHz book and started it up, I get a DOS like looking window that gives me the BootROM build date and time. Below that it says,
"Welcome to Open Firmware.
To continue booting, type "mac-boot" and press return. To shut down, type "shut-down" and press return.
Kind of cool, but since I don't know anything about open firmware, I am stuck with a computer I cannot use.