Cmos battery question

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Hi all..... Do I have to shut down my PC to replace the bios battery and
  if I do will I lose all my bios settings when I remove the battery to
install a new one?


Re: Cmos battery question

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You will most likely loose the settings but it depends on the motherboard in
use.   A few of them use either power from the power supply and or the
battery but most use just the battery.

There are some CMOS saving programs around that might copy the settings to a
floppy but they only work correctly if the one you use is written to support
your particular motherboard.  You might be able to locate one of these from
the web site supporting the motherboard.

To be safe I would take the time to go through the all of the menu screens
and write down the settings.  Remember to scroll down all the way to the
bottom of the page as some of them might have more lines of text than what
fits on the screen.

When your finished I would then tape a copy of the settings to the inside of
your case for future troubleshooting.  Some place that does not block air
flow or fans.

Re: Cmos battery question

Newfdog wrote:
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    If you do it carefully while power is on, you will NOT lose the
something conductive such as the battery while power is on, you risk
damaging the MB.  Placing a cloth over the area around the battery
during the removal and replacement serves as a means of avoiding such
damage should something fall on the MB.

    If you do not feel comfortable in doing this, try a search for and use it to save the settings to a floppy or the HD.
They then can be restored should the need arise.

Re: Cmos battery question

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The safest way to do this is with the computer powered off and
unplugged. That guarantees there is no +5VSB alive in the computer.
If you are worried about static electricity, then leaving the
computer plugged into a power strip which is switched off, would
leave the safety ground connected to the computer. In any case,
make sure the green LED on the motherboard is not lit - it
indicates the status of +5VSB and it should be off.

A previous poster who tested this, found that his settings were
still valid, after replacing the battery. The secret is not
spending too much time in the battery-less state. If you fumble the
battery, and somehow short the battery socket contacts together,
that could be enough to drain what little energy is left in the bypass
capacitor, in which case you'll lose the settings. The CMOS only
draws a few microamps, and that is why it can keep the settings
if you don't leave it without a battery for too long.

As the other posters suggest, write down the settings just in case.
If the settings are important to you, there might be other occasions
where you will need to restore the settings, so recording them now
will make some future job that much easier. For example, if you
ever need to clear the CMOS due to some other problem. A digital
camera is one way to record screen settings without working up
much of a sweat.


Re: Cmos battery question

On Tue, 07 Feb 2006 15:36:04 GMT, Newfdog

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1.  Use to save the CMOS settings to a disk file.
2.  Shut down the PC.
3.  Change the battery.
4.  Boot the PC and check the CMOS settings. If they look OK,
                stop here, otherwise go to step Five.

5.  Reload the saved CMOS settings. Check the settings again.

   The first time that you use CMOS14, I would write down the CMOS
   settings just in case you have a "blurp".

    Also, keep the saved settings file in case something else screws
    up the settings.

    It's saved my bacon many times.



Re: Cmos battery question

Newfdog wrote:
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Thanks for all the info guys.


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