What is the function of the CMOS battery?
Just as a watch battery keeps time ticking, the CMOS battery helps preserve the computer’s calendar and hardware settings when the computer is turned off. CMOS batteries tend to last for four to seven years before replacements are needed.FunctionThe computer’s CMOS, or complementary metal oxide semiconductors, consist of battery-powered microchips that house the basic input/output settings (BIOS) on the motherboard. The CMOS also maintains the system calendar.System Date and TimeThe CMOS battery allows the computer to remember the current time and date when it is offline.Hardware SettingsThe CMOS battery retains the BIOS configurations when the system goes offline. The BIOS controls the interaction and customization of hardware components and preserves the boot order of hard drives, floppy drives and optical devices.TypesThe most common type of CMOS battery, the CR2032, is the size and shape of a dime. Older computers used barrel-shaped CMOS batteries that were soldered directly onto t