cmos battery

[Braincramp]

My little watch battery is at least four years old and I'm gonna replace it. My question: when? Do I do it with the system 'on' and risk major electocutionary-type injury or, worse, damage to the system. Or unplug it and risk losing all bios settings when I pull the battery?
Thanks!

[YODA74]

1. Boot your PC and enter its setup mode
2. Write down all of the settings from the various menus.
3. Power off your PC.
4. Open the case and locate the battery on the motherboard.
5. Obtain a replacement battery from a local or online computer parts dealer or Radio Shack.
6. Remove the old battery and replace it with the new one.
7. Document the date you replaced the battery.
8. Replace the case and power on the PC.
9. Enter your PC's setup mode.
10. Reenter the settings you have written down from the various setup menus.

[Braincramp]

I'll do it. Thanks!

[Inka]

For some reason I thought the BIOS chip held its setting for about 20 minutes.. long enough to change a battery anyway? am I mistaken or is it a belts n braces approach to write down all the settings?

[YODA74]

if you're really fast, you may be able to replace the battery and not lose any settings. There will be a residual charge left in the CMOS that MAY hold the data for a few minutes. If you're fast, this will save time, but don't rely on this. And Not no 20 minutes

[david eaton]

Yes, in theory, the setting should be retained.

BUT would you trust it to?

I have just changed the battery in my machine and I had all the settings written down. Nearly needed them too!
B*** motherboard needs ALL the expansion cards removed to get at the **** battery!

Where these computers are concerned, I prefer belt, braces and an emergency bit of string :D

David

[Inka]

Noted thx for the clarification!