Nvidia compatibility and monitors

Welcome to the forum, Tristan. This is actually a very great question. The short story is that Nvidia recently opened their GPU's to utilize AMD's FreeSync technology. While you can technically enable G-Sync Compatible mode on any Freesync monitor, not all of them will work without hiccups unless officially certified by Nvidia. Here is a list of monitors that Nvidia has officially certified: https://www.nvidia.com/en-us/geforce/products/g-sync-monitors/specs/. If the monitor is not on this list, it doesn't mean that it's not going to work or that it's automatically going to have issues, just that Nvidia hasn't tested it or that it may not meet a very specific requirement to receive their official certification.

MSI has released a list of monitors that they tested and claim they had no issues:


Now I cannot vouch for MSI as I have not personally used their Freesync monitors under Nvidia's G-Sync compatible mode, but I have used quite a few Freesync monitors that were not certified for G-Sync compatibility and had no issues, so your mileage may vary. 

I hope this helps narrow down your search a little.