Hi! Matthew Bellstedt, Welcome to the Microsoft Community!I realize that you've encountered a problem with The computer can only be displayed as a half screen, am I understanding correctly? If I understand it wrong . Please point it out. Can you provide me with a photo or screenshot of your computer's display so that I can pinpoint the problem and provide you with a more appropriate solution?
Based on the description you provided, I'm inclined to think that the problem may be caused by some third-party software, you can try the following to see if the problem still exists:
- If you have some third-party wallpaper software installed on your computer, please try to uninstall it to see if the problem still exists.
- Try adjusting the display ratio and scaling on your computer in Start>Settings>System>Display>Try changing your Display resolution and scale
- If none of the above options solves your problem, you can also try to perform a clean boot to see if the problem still exists, please refer to :How to perform a clean boot in Windows - Microsoft Support, this is a mode of disabling third-party services or software, which could help rule out the interference of these elements. Disclaimer: A “clean boot” starts Windows with a minimal set of drivers and startup programs. It helps to determine whether a background program is interfering with your game or program and to isolate the cause of a problem.These steps of "clean boot" might look complicated at first glance. However, to avoid any trouble for you, please follow them in order and step-by-step so that it will help you get you back on track.
Feel free to post back if you need further assistance.Thank you for your understanding and patience and I look forward to hearing from you.Best RegardsEddy | Microsoft Community Support Specialist