hello. I just switched to Linux but GTA 5 isnt running as smooth as it runs on Windows 10.
I got like 40-60 fps on Windows, but on Linux I have like 40 fps and it drops to 20 - 30 several times.
can someone help me?

latest stable nvidia drivers installed (430.14, I guess)
gta v installed form Steam with Steam Play/Proton 4.2-7

my pc:
i3 4170
gtx 750ti 2gb
12GB RAM

gta v settings:
all set on lowest
1920x1080

Hi,
shouldn't you be asking this question in a more Linuxy place?

Good question.
Specially considering that he's asking questions about a game which isn't even sold on GOG, and he hasn't bought a single game here.

We've never seen you before, yet you ask for help with a game that's not sold here at all and that doesn't even work with Linux natively. You don't even own any games here.

This is... odd.

Well, I hear Nvidia's Linux drivers are not as good as their Windows drivers. No more ideas than that, sorry.

It sure looks super suspicious for a first post on these forums but I rest my hammer, for now.

Ask the support. They will tell you what you can do with the game.

https://www.protondb.com/app/271590

This wont happen to be you, does it?

That's a pretty low spec machine, so if Linux isn't natively supported and therefore more resource heavy it pretty much explains the difference right there. Ask on a forum more focused on this game (or Linux) though and you might get a better answer.