What Can Happen If You Remove The CMOS Battery?

Do Not Remove Your CMOS Battery

Learn why the CMOS battery is so important to your computer.

Episode #12-04 released on September 16, 2021

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The CMOS battery is a very important source of power for just about every device, especially computers and laptops. They maintain power to the CMOS which contains a lot of necessary information to allows your computer to boot reliably and securely, each and every time. So, what happens if you remove the battery and there is no power to the computer?

The first thing that is lost is the time and date, although, this does not really matter as the second the computer powers and the operating system loads, the time will be fixed.

The second thing that will happen, is all settings related to boot order, overclocks, etc. will disappear. This is a useful trick if you ever have a computer that absolutely refuses to boot.

The third thing that can happen is that your PK Keys for secure boot disappear which will prevent most operating systems from being able to boot until you disable this. This may be an issue for Windows 11.

If you have encryption keys embedded in the UEFI bios, clearing the CMOS may erase these, too. That would make the drives unreadable, thankfully, this is rare for now.

And, if you use RAID, you will lose the raid settings and access to any raid array.

In the case of Raid Arrays, PK Keys, etc. you can back these up and load them back into your bios. Having backups, even for these is important. Having a backup of a working bios configuration is the best thing you can do for yourself.

But guess what, you do not need to remove your CMOS battery to run into these issues. The CMOS battery will eventually die, and your computer loses power after the CMOS battery dies, then all your settings will disappear. And, many mainboards, also, come with a clear CMOS button, if you accidently hit this, you will, also, clear your CMOS.

To avoid any issues, always, always, make backups of settings and security keys for your bios, you will thank me later.

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

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