When you found CMOS checksum error message this indicates that your BIOS data is reset, usually, there are 2 conditions:
1. We need to set the BIOS configuration using key F2, or sometimes we can continue by pressing F2 key. If after setting the BIOS configuration and you restart the computer still found the same error it indicates that the batter is not functioned properly.
2. CMOS battery is weak or dead. You have to replace it with the new one.
Replacing CMOS battery will need to open computer casing so you need to prepare a screwdriver and a new CR 2032 battery. Some computers still using the green battery that soldered into the motherboard. You need to prepare the solder to replace the battery.
|Modern computers using button battery CR2032 to maintain the BIOS data.|
Besides CMOS checksum error message it will also reset all your BIOS setting thus every time you turn on the computer it will ask setup BIOS before you can continue working with the computer, this is very annoying.
If you don’t replace the battery there is a possibility that the batter will swell and will produce a liquid that will ruin the motherboard and make further damage.
In most cases after replacing the battery, CMOS checksum error message will disappear. However, if you still see the error it could be a hardware problem. Maybe there is corrosion on the mainboard or other problems.