Ethan Benson wrote:
On Sun, Nov 04, 2001 at 09:15:43AM +0100, Michel Lanners wrote:FWIW, I don't think recent PowerBooks even have a PRAM battery; I think they only have the main battery. Older ones (my PB500 comes to mind) had a small watch-style battery for clock and nvram backup.well i think nvram settings are stored in flash on newworlds, so it doesn't need a battery to maintain, but the RTC still does. apparently apple doesn't care about the clock.
Old PowerBooks had a battery (nonrechargable) that held P-RAM and RTCwhen the main-battery was removed or depleted. This battery last for the lifetime of the PowerBook. That´s why you can put an old Powerbook in the cellar for some month the main-battery will be empty but P-RAM and RTC will still be in a good condition.
AFAIK since the Pismo (maybe Lombard or Wallstreet), the Powerbooks have a little rechargable batterie that only holds RAM-content, NVRAM and RTC for a few minutes when it is put to sleep, but it is enough to change an empty main-battery with a full loaded one. If you remove the main-battery from this PowerBooks and put it in the cellar for a few days, RTC and NVRAM-settings will be gone (reset to defaults). Some won´t even startup if you put in a new main-battery or plug in the power-adaptor. You have to wait a few hours with the power-adapter pluged in, so the little backup-battery will load a bit. Then the new Powerbooks are able to startup. But iBooks do not have this battery. If you remove the main-battery the NVRAM-settings and RTC are toasted in a few seconds or minutes.
Bye, Christoph