ehhh... zap the nvram, but I don't recall how. I however DO recall that if your NVram for whatever reason gets screwed up your falcon gets the symptoms as you describe...
Another one: The nv ram needs costant power, so when your falc is off it gets its power from a battery. The battery is located inside the RTC chip (the big black lego like one). Perhaps you can find one in an old PC; I don't know how to diagnose if the battery is empty, Maybe someone else remembers all the details?