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How can I save my BIOS settings before replacing the CMOS battery?


Hi, Leo. The system battery in my 10-year-old Dell desktop computer can no
longer supply enough energy for the clock to keep the right time. I’m sure
other functions are not working right as well. The Dell handbook says to copy
15 system screens before replacing the battery. Is that over caution or a real
need? I continue to enjoy your newsletter and look forward to your answer if
and when you get a chance.

In this excerpt from
Answercast #30
, I suggest an easy way to grab images of BIOS settings, just
in case things go wrong after changing a battery.


Recording the settings

Boy! So I want to clarify that when you say, “Dell says to copy 15 system screens,” what it’s asking you to do is to record the settings in 15 different screens presented by your system BIOS; because those are the settings that are going to get lost or reset when you remove the battery from your motherboard when you replace the battery.

Is it overcautious? Boy, it’s not something I’ve ever done to be honest.

  • I’ve always replaced the battery;

  • Let the BIOS basically rediscover what the system is like;

  • Reset the time myself by hand,

  • And then gotten on with my life.

Things just seem to work.

There’s a risk

Now, unfortunately, I can’t guarantee that’s always going to work. I mean, it’s one of those things where it’s very possible that there’s an important BIOS setting that you would lose when you replace the battery. You would not then be able to figure out what that setting was.

Take a picture

So here’s my recommendation:

  • Grab a digital camera; take a picture of each of those 15 screens; save them, then ignore them.

Replace the battery; see what happens.

If something isn’t working properly, then take the time to compare the 15 pictures of the screen with the 15 different screens. You’ll see if there’s a setting that you may have missed or that may have been important.

  • At a minimum, you’ve saved the settings in a way that you can then go back and recover from if you need them… and, in a way that’s not horrible!

  • You didn’t have to go through and write down 15 pages of information, or do something else silly!

This is a wonderful application, even for your cell phone camera (if it will take a relatively clear picture of your computer screen). Just do that; save the pictures somewhere as a reference for what all of the settings were before you replaced the battery, and then replace the battery.

Next from Answercast 30 – Am I too old to start learning an IT career?

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1 thought on “How can I save my BIOS settings before replacing the CMOS battery?”

  1. Good Advice!!
    Taking pictures of each step also works in other situations, like replacing any innards in your computer.


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