Purpose of the motherboard battery

[Alpha]

I was recently troubleshooting my brother’s computer, which wasn’t displaying anything. I checked and tightened some wires, and it started working again. While doing so, I noticed a battery on the motherboard. What is the purpose of this battery, and what kind of issues can it cause if it becomes weak or dies?

[handyandy]

Hi and welcome to the forum!!! That is the CMOS battery. It maintains just enough power to allow the motherboard to remember some key settings even without power attached to the computer. Often BIOS will notify if the battery is weak. They last for years and are cheap to replace.

[Alpha]

Hi! Thanks for the warm welcome and for the explanation!

I was just wondering if that could be causing issues with my brother's computer, but now I don’t think so. As far as I know, there was no warning, and after checking the wires, the computer seems to be working fine. But it’s really helpful to understand the purpose of the battery for future reference. Thanks again!