What Happens When You Remove The CMOS Battery?

This is why you do not want to remove the CMOS battery

Learn how to avoid issues with the CMOS battery and what you need to recover from CMOS battery failure.

Episode #12-31 released on April 8, 2022

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Just a note, if your computer is in otherwise working order, please make a backup of the bios configurations and pk keys. This is especially important for any operating system that relies on secure boot.

At one point, all CMOS batteries will die, and the associated settings of the mainboard will be erased entirely which will cause the computer to stop booting correcting, change all fan settings to default, etc.

However, knowing all the settings may mean nothing to you, and you may be wondering what happens at this point. For starters, especially for operating systems like Windows 8, 10 and 11, your computer may be unable to boot if secure boot was enabled. Especially Windows 11, which requires explicitly the use of secure boot. In the case of Windows 8 and 10, you can disable secure boot and boot into Windows. And all this presumes the boot order of your computer follows the defaults assigned by the manufacture and mainboard. If it does not, then you will have to manually select the boot drive just to attempt at booting your computer.

There would be further issue if you did not have the password to decrypt the drive in some cases because drive encryption via TPM is required for Windows 11. You would have to have the decryption key, pk keys and a backup of the bios just to restore the system to working order. And this means that having backups are definitely going to be important for all your data, and all settings related to every computer you have from this point on. Especially with Windows 11 and the anti-end user stance Microsoft has taken with the introduction of such restrictive operating system policies.

Beyond getting into your operating system, settings related to cooling, modifications made to RAM timings, overclocking settings, etc. will all be reset. If you do not have those settings saved, you will have to manually restore all those settings yourself. Definitely a good idea to backup any bios settings then.

Now, you may be asking if there is a way to change the battery without losing any of the settings, and the answer is yes, but only if the system is powered and there runs the risk of accidently shorting something if the battery goes flying and connects to traces, probe points, etc. So, in this case, use absolutely extreme caution. It would be preferable to change the battery only after you made a backup of the settings, regardless, just in case your computer loses power while the battery is out, like if you experience a black out. And remember, to only do this once the computer is off and plugged in.

Host : Steve Smith | Music : | Editor : Steve Smith | Producer : Zed Axis Dot Net

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