I use gamemode to run mine on e-cores only because hyperthreading causes it to freeze after loading in (either for the first time, or when changing maps). It was usually temporary, but once it just froze my entire system, and when I loaded back in, I was in the middle of quicksand and my copter was gone. :( Turning off hyperthreading also solves that problem, but that would affect everything else I run.

Similar specs, I was getting full lock-ups after 1-3hrs.

GPU: AMD Radeon RX 6950 XT CPU : AMD Ryzen 7 3700X 8-Core Ram: 32gb

Enabled a setting in game to always reserve one cpu core for basic sys functions and haven't crashed since. (Haven't played the recent patches either though)

Weird, mine has been fine on a mix of linux computers, one had some power or thermal issues resulting in instant power off, but the game works. Lord knows ive spent more than a few 5 hr runs just building the base lol.

Yep! Similar freeze after some period of playing, haven't found a solution yet.

GPU: NVIDIA RTX 3070 CPU: AMD Ryzen 7 5700X3D RAM: 32GB SSD

I'll update Proton version detail later today and report back on the suggested fixes in this thread.

Do you have steam overlay disabled? If so try the LD_PRELOAD workaround by entering:

LD_PRELOAD="" %command%

in the game's launch options.

This was supposed to be fixed by now but I still have the issue intermittently with some games. Usually they just start lagging, but rarely they will full crash.

Please update once you confirm it does or doesn't work.

EDIT: More about what this variable does, for the curious: https://wiki.archlinux.org/title/Steam/Troubleshooting