Cmos Checksum Bad – Date Time Not Set

Now, it is just a matter of putting the cover and cables back. If you’re getting errors when you boot your PC, the problem may be nothing more than a dead CMOS battery. Turn your PC on and try to enter BIOS settings by pressing the BIOS key as the system is about to start. The BIOS key is typically displayed on the boot screen, saying “Press ___ to enter Setup.” or something similar.

The CMOS Checksum Error is a problem which affects users of many different Windows versions and it often appears out of nowhere. The problem appears during the BIOS boot screen and it prevents your computer from loading the operating system at all. After completion of a BIOS update, you may encounter a CMOS Checksum error or other problem.

This error is generated by the bios firmware rather than Operating System. If bios recovery and/or resetting bios to default setting doesn’t fix this problem, try to rollback to the previous bios version which worked good (do this using bios recovery method). If, after following Leon’s advice, the BIOS continues to display the CMOS Checksum Error message, it means that you need to replace the CR2032 battery on the motherboard.

When the battery is depleted, CMOS cannot store information anymore. CMOS is a battery-powered semiconductor chip on the motherboard, storing all BIOS-related information. This is the first program to run when the user turns on the computer. CMOS is responsible for creating and testing hardware, such as CPU, memory, keyboard, mouse, etc.

If this happens, enter the BIOS Setup and press F9 to load factory defaults. The CMOS checksum error is an issue that affects many users of different versions of Windows, and it often occurs anywhere.

  • You might also want to clear CMOS to reset a BIOS or system-level password, or if you’ve been making changes to BIOS that you suspect have now caused some kind of problem.
  • When you are finished with your changes, you should choose "Save Changes" and exit.
  • Be very careful when making changes to setup.
  • It should be easy enough, however, as long as you can find that reset option.
  • The directions linked above detail how to access your BIOS utility but don’t specifically demonstrate how to clear the CMOS in your BIOS utility.
  • Incorrect settings may keep your computer from booting.

The good news is that replacing the CMOS battery is quite simple. Make sure all power is off on your machine and unplug all cables on your CPU case (make sure you remember where all of them go for when you plug them back in). Open the case and you will see the battery on the motherboard. Carefully take it out and replace it with a new one.

Reset Bios

If you are thinking you won’t be able to do it properly, then contact a computer technician. Sometimes when you shut down your computer directly from the power button without following the traditional steps of shutting down a computer, it disrupts your computer. That’s why the CMOS Checksum error welcomes you the next time you start your computer.

One of the more common causes of CMOS Checksum errors is also the simplest to solve. It is the battery that powers the CMOS battery as a normal clock battery and will simply come out of it.

In this scenario, you only have to follow the on-screen instructions. Hopefully, the error gets solved, and you restart your computer successfully. The CMOS checksum error is a standard system error that happens in Windows computers. The error appears when you try to start your computer. And finally in my opinion, Resetting or reinstalling Windows, will not fix CMOS checksum error.