m15 R1, GeForce RTX 2070, G-Sync

Hi 

I have an Alienware m15 R1 laptop (bought on July 10, 2019) with the Nvidia GeForce RTX 2070 8GB GDDR6 Max-Q. I want to use an external monitor for playing games occasionally.  

But I can't seem to find out whether my machine is capable of supporting G-Sync as I want to go for a screen with a higher refresh rate than 60Hz.

How do I check this as I don't want to research what monitor to get only to wind up being disappointed that my laptop does not support G-Sync, despite having a fairly recent Nvidia GFX card and a mDP connection.

Any help or advice will be appreciated.