What is the battery for on computer motherboard?

The small battery you see on a computer motherboard is called the CMOS battery or BIOS battery. Its main job is to power the CMOS chip, which stores important system settings like the time, date, and some hardware configurations.

Do mini PCs' motherboard have CMOS battery?

Yes, they have. Even though the mini PCs (like Blackview budget mini PC) are very small, but they have all parts the traditional desktops have, like CPU, RAM memory stick, integrated circuit, and more. They are simply smaller versions of desktop computers.

What the CMOS battery does?

• Keeps Time and Date: Even when your computer is off, the CMOS battery helps the system keep track of the correct time and date.
• Saves System Settings: It also saves basic settings for your computer's hardware, like which drive to start first (boot order).
• Prevents Data Loss: Without this battery, your computer would lose these settings every time you turn it off, and you'd have to set them again when you restart.

Relationship with BIOS

The BIOS (Basic Input/Output System) is the first software that runs when you turn on your computer. It helps the computer boot up and checks that all the hardware is working properly. The CMOS battery helps keep the BIOS settings saved, like boot order or system time, so they don’t reset every time the computer is powered off.

CMOS batteries usually last for years. Without a working CMOS battery, your computer might still work, but you could see messages like “CMOS checksum error” or the system clock resetting every time you turn on the PC. In this case, you would need to replace the battery.