changing the CMOS battery

[wylbur]

1. For a Thinkpad 600, the CMOS battery consists of a generic CR2025
3-volt lithium "coin" battery that's attached to wires by means of
adhesive metal tabs. One could just purchase a new CR2025 battery,
unplug the existing CMOS battery assembly, peel the metal tabs off the
old battery and reattach them to the new battery, then plug the
assembly back in.
Is the CMOS battery for a T23 designed the same way? If yes, what is
the battery type for the T23? is it also a CR2025?
(I suppose I could take out the CMOS battery and look at it to find
out, but I'd rather purchase a new battery and have it on hand
*before* I try to remove the old battery so that I can switch the
battery with a minimum of delay. The longer I leave the computer
without the CMOS battery in place, the more I worry about the
possibility that some setting might get corrupted).

2. I searched the newsgroup archives for interesting caveats
pertaining to the changing of the CMOS battery on a Thinkpad, and made
a disturbing discovery that many people (especially those who bought
their computer used or refurbished) who had changed their CMOS battery
got locked out of using their computer because there was some latent
supervisor password (SVP) that had gotten "triggered".
If you've never set any passwords on your computer, and everytime you
power it on it never prompts you for any passwords, can you assume
from this alone that you can safely change the CMOS battery?
Or is it possible that if a computer had a supervisor password set at
some time in the past but later deactivated, or a SVP was created
accidentally as a result of a "glitch" or spike, even though the
computer no longer prompts for any passwords when it's powered-on this
SVP is still lurking in the shadows and will re-activate when some
event occurs that can be remotely interpreted as "tampering" (such as
removing the CMOS battery)? If this is possible, how can one find out
if there's a latent SVP? and how would it be removed?

[Bob Collins]

I think the T23 is the same as my T22. It uses a CR2032. I just had mine replaced by IBM as my time and date was changed after each boot. Finally on the last boot, the HD was "Not Found". They replaced the battery under warranty. I would assume you may still have warranty.

Yes, I would think you could peel and stick the old contacts, however I am not sure how you will get good adhesion to the new battery without some good shrinkwrap type thing or solder/spot-weld.

I do not think anything that will get lost without a CMOS battery would really be time dependant. I think once you pull the battery, the settings are lost. YMMV

As for the reappearing passwords, I cannot help. Sorry.