Got this little gem in my email.
I can't tell you how many times my screen has frozen and I resorted to Restart (losing all the work I did up to the freeze). Had I known this trick, the air in the room would have had a far less blue tint.
So much for cliff hangers...
"To reset your graphics drivers when your computer is frozen, press the following key combination: Win + Ctrl + Shift + B ." - MUO
What's so great about this command is that all the apps currently open remain unaffected: Only your video driver is restarted.
"This only works on Windows 8 and newer, so Windows 7 users can't take advantage of it. However, it will work no matter what kind of video card you have. Nvidia, AMD, and even Intel integrated graphics will reset with this shortcut." - ibid
There are other reasons why computers freeze. I suggest reading the article because it has good tips on how to progress in troubleshooting the freeze. Here's a link to read about further steps to take.
How to stop an app without Task Manager: https://www.makeuseof.com/tag/how-to-kill-unresponsive-programs-without-the-task-manager/
How to open task manager to stop nonresponding programs: Ctrl + Shift + Esc .