Can I Use Dual Monitors with Different Refresh Rates on Linux Mint?

Just a heads up, if you're sticking with Mint, the Cinnamon desktop environment is based on X11, which doesn't support mixed refresh rates. Switching to a desktop that supports Wayland, like KDE Plasma, might resolve your issues. It's worth a try if you want to keep Mint!

You've got it right; Mint on X11 doesn't deal well with different refresh rates. If you’re open to it, look into other distributions or desktop environments that support Wayland for a smoother experience.

I've faced a similar issue with different resolutions and refresh rates, especially when using a docking station. I found that while Linux Mint struggles with multi-monitor setups using Wayland, CachyOS with KDE Plasma handled it great for me. I was able to get fractional scaling to work, and all my monitors ran at their respective refresh rates. Just make sure you install the necessary drivers for any docking stations you might have. I did hit a bug where my programs opened on the docking station monitor instead of my main one, but it was manageable.

Actually, for quite some time now, Linux handles mixed refresh rates better than before. However, since you're using an Nvidia GPU, that’s where things get tricky. You might run into issues since Nvidia's drivers can be a bit finicky with dual monitor setups. I'd recommend checking out other desktop environments that use Wayland, like KDE Plasma, as they tend to manage different refresh rates more effectively.