CMOS or Complementary Metal Oxide Semiconductor is a semiconductor chip inside a PC that stores information like BIOS settings, time and date, etc. Whenever there is a data conflict between the BIOS and the CMOS data, the CMOS checksum error will be displayed.
Why am I getting a CMOS checksum error?
So what are the reasons that could lead to a conflict between BIOS and CMOS data on your PC? Well, there are various issues that can trigger the CMOS checksum error, some of which can be easily fixed and some may even require hardware replacement. Let's take a look:
Improper shutdown of the PC
If you didn't shut down your PC properly, you may get the checksum error. This is because an improper shutdown did not give the CPU enough time to generate a checksum number. And as we know, if there is a conflict between the checksum numbers, you will get this error.
Make sure you shut down your PC properly by going up energia option in the Start menu. Once the shutdown process has begun, be sure to disconnect your PC from the power source only when the monitor and CPU shut down by themselves.
The CMOS battery may be exhausted
The PC's CMOS chip does not work with the standard power input, but requires a small additional battery to function. When the battery power is completely depleted, the CMOS cannot generate a checksum number. Again there is a conflict between the BIOS and CMOS checksum values, causing the checksum error.
Corrupted / outdated BIOS
Problems with the BIOS on your PC could also be the reason you are getting the error. If the BIOS installed on your PC is not up to date, it may conflict with the latest versions of the operating system. While rare, you may also get this error due to a corrupted BIOS.
If a power surge occurs and the PC unexpectedly shuts down, a checksum error may be displayed because the CMOS cannot generate a checksum number.
If your motherboard is damaged
A motherboard that has been physically damaged could cause various problems, including the CMOS checksum error. Sometimes even the smallest damage can bring things downhill.
Now that you know what the reasons for this error are, let's find out how to fix CMOS checksum error in Windows 10.
Solution 1: restart your PC
The first step to solve this problem is to restart your PC. As mentioned above, improper shutdown could lead to a conflict between the CMOS and the PC's BIOS. So, restart your PC properly and see if this solves the problem.
In most cases, a simple restart might work, but if not, the reason behind the problem could be something else.
Solution 2: Check if the CMOS battery is installed correctly
It is important that CMOS is always running while using the computer. As we know that CMOS works on a small battery, any problems could lead to problems like CMOS checksum error.
The CMOS battery may have slipped out of place and cause all problems. Although small bumps can hardly move the battery, you will need to make sure.
If you're using a desktop PC, finding the CMOS is really simple. It is a small battery located on the motherboard of the CPU. However, finding the battery in laptops could be a problem. For this, you can always Google the location of the CMOS battery on your laptop by entering the brand and model name of your laptop.
If you see that the battery needs to be adjusted, fix it in the defined position and then restart your PC. This could solve the problem.
Solution 3: Replace the CMOS battery
After checking the location of the CMOS battery to see if it is seated correctly if you continue to get the checksum error in Windows 10, the CMOS battery may be dead.
It is recommended that you always have a pair of CMOS batteries on hand. They don't cost much and replacing them isn't a daunting task. Anyone with minimal knowledge of PC hardware can proceed with this solution.
Go ahead and replace the battery with a new one. As you do this, make sure you have the battery securely in place.
After doing that, restart your PC and check if the CMOS checksum error is fixed. If not, try the next solution.
Solution 4: Reset your PC's BIOS
Resetting your PC's BIOS to factory settings may help you solve the problem. Your PC's BIOS may be corrupted. Events such as a sudden power surge or even a malware attack could cause motherboard damage or malfunctions.
To eliminate this probability, you can perform a BIOS recovery on your PC. If you do, the BIOS will update as new and may fix the problem. But how to reset the BIOS?
For this, you will need to enter the BIOS setup on your computer.
Restart your PC and as soon as it turns on, you will need to press the F2, F10, F11 or F12 keys on your keyboard. The key you must press to enter the setup is defined by the manufacturer and you can see the key you must press as soon as the startup screen appears on the monitor.
Once you enter the BIOS setup, you will find the option to reset the BIOS. Press the specified key to reset. The recovery key varies again by manufacturers and if you can't find the option, I recommend that you check your motherboard user manual.
Once you understand how, proceed with a BIOS recovery. After rebooting, restart your PC and see if the CMOS checksum error still appears.
Solution 5: update your PC's BIOS
Your PC may not restart and even have problems if your BIOS is out of date. In that case, you will need to make sure that the updated version of the BIOS is installed on your PC. If you are unsure, you can always continue with the BIOS update. If there is an update available, continue, if not, try the next step.
There are a couple of methods you can follow to update the BIOS on your PC. The first is through the BIOS setup menu. Follow the steps provided in the previous method to enter the BIOS menu. When you are there, follow your motherboard's user manual to update the BIOS to the latest version. This is one way to update the BIOS.
The other way to update the BIOS on your PC is to visit the website of the manufacturer of the motherboard you are using. Here, select the motherboard model you have installed on your PC and download the latest version of the BIOS update. After downloading the update, run it on your PC to start the BIOS update.
Once you've successfully updated the BIOS on your PC, go ahead and restart it. After the PC reboots successfully, check if you are getting the CMOS checksum error.
Solution 6: Consult an IT technician
Your PC motherboard is not an easy device to manage. If none of the above methods worked to get rid of the CMOS checksum error in Windows 10, you may want to consult a technician who is good with computers, especially motherboards.
A technician can examine the PC hardware and software to see what exactly is causing the checksum error on the PC.
While it's pretty obvious that some technicians may go ahead and try to deceive you, I recommend that you first consult with someone (perhaps a friend) who is good with computers and has experience dealing with motherboard problems.
The maximum expense that can be expected when addressing this problem with the help of a technician is the cost of the motherboard along with the service costs.
Beware of technicians who may scam you. Always negotiate the repair price needed to get your PC up and running smoothly again.
Consulting the device manufacturer's service center is always a good choice.
Solution 7: replacing the motherboard
Be sure to check your PC for physical damage to the motherboard. If you are using a desktop PC, the chances of damaging the motherboard are greater than they normally are with laptops. In any case, if the above methods don't fix the problem, go ahead and check your PC motherboard for damage, even the smallest ones.
If you find damage that compromises the chips or motherboard hardware, go ahead and have a technician check it out. If nothing can be done to save the motherboard, replace it. But always make sure the motherboard really needs to be replaced.
Ultimately, the reason you are getting a CMOS checksum error on your PC should be mainly motherboard battery issues. It is unlikely that you will need any kind of replacement. But if you do and situations justify it, you'll need to consider replacing.