I've been working on converting my gaming PC to Linux for a few weeks, but everything is running, but it all is just a little jankier than I would like.
I have an 8th gen Intel i7 and an Rtx 2070, running Arch linux.
Sometimes I boot up and my mouse doesn't work and I have to restart. Sometimes I launch games and they just don't launch right.
It feels like I'm doing a lot of work for no benefit. In fact, Elden ring runs way worse on my Linux partition than my Windows partition.
I've tried GE proton, gamemode, steam compatibility, everything... I'm sorry but I'm going to have to stick with Windows for gaming.
sounds like your problem is likely a combo of trying bare arch and also an nvidia card. i'd recommend Pop!OS as i hear it's the best out of the box experience for nvidia owners, and if you want to stay arch based i'd try EndeavourOS as it's arguably the most mature and stable arch based distro today, it's what i use but i also have amd not nvidia so i can't speak for the nvidia experience for endeavour. maybe you want to wait a while before you try again just so you're not burning out on the frustration, too. good luck!
I'm guessing you're running either the nvidia open source drivers (way worse performance) or you don't have graphics switching configured and it's using your GPU's iGPU (way way worse performance).
Bigger distros like Mint will probably configure that for you.
nvidia only very recently opened up their drivers to open source dev, so the open source drivers available right now are still based on reverse engineering and they don't work super great. there are proprietary drivers from nvidia but they are not easy to install and configure and popos handles that for you on install.