Hi there kdy,
I know this performance hit is no fun, you just want to play the game on an external monitor on this mobile computer. Right now, we know of the issue and hope to have a fix in the future. I have no information regarding that though, all I have to offer is a workaround we offer for users who want to use this type of setup.
The issue is with graphics switching when using an external monitor on a laptop that has a dedicated Nvida GPU.
- The Workaround we have:
- Press Windows + P
- Select the Monitor you wish to play the game on as the only monitor
- Launch the game
- Press Windows + P
- Select Extend
This should get things working for you my friend!
/Nathardrick