Your Windows 10 laptop's horizontal green line may occur for several reasons. Identifying if the green line results from a hardware malfunction or software bug are crucial for practical problem-solving. To solve Windows 10 green lines on screen, follow the below steps:

1. Open cmd and run it as an administrator. 
2. Now, execute the command: 'wmic bios get smbiosbiosversion.' The BIOS or UEFI firmware that is installed on your computer will be shown by this command.
3. Open your laptop's OEM website once you have the BIOS version.
4. Go to the download center and then enter the information for your laptop.
5. Check the download page to see whether your laptop has a BIOS update available.
6. Extract the Zip file after downloading the BIOS.
7. To upgrade the BIOS, open the readme.txt file and follow the directions.

Read more about Windows 10 green lines on screen  :  https://promptresolve.com/operating-system/fix-green-lines-on-windows-10/