Can i update the GoG Version of Q2 with the RTX update from Nvidia or does it only works with Quake 2 Steam?

Yes you can do that. It will work just fine. But to get a good frame rate with RTX active you need a monster of a PC.

This is about Quake 2. Even if RTX halves the frame rate - then there's still A LOT of fps left.


Oh, and good frame rate is subjective. I consider 60 fps more than good enough. Same thing for a stable 30 fps in some games.