When catching up with hardware performance for Linux gaming, I always browse phoronix, try to find a few comparisons from different years to see how the card looked like in comparison to other options. There might be some sleepers now no-one remembers about, that you magically have an option to buy. Think which game in the comparisons might have similar requirements to what you want to play and see how the card/cpu did on the settings you find agreeable/non-agreeable/perfect
Don't go into its forum, though. There be dragons
Maybe recently it started to change with NVIDIA opening their drivers but for years we've been second class citizens for them. Personally I say "fuck NVIDIA"
If you decide to go AMD, definitely explore the landscape of fan controllers. I use corectl but maybe you would prefer something else (this is Arch wiki, but should be fine for other distros too)
I would not be surprised if in a month it turns out a bunch of those don't match with the crimes