If you look at the log file, you can see information about the crash with "Offset = 0x003C91CC", which means "Out of video memory."
But you have ~4GB of video memory available and this shouldn't be a problem.
The only suspicion that can be is that the server is abusing VRAM usage (lack of optimization can be such a reason) and because of this, the game crashes/freezes.
For objectivity, it would be nice if you went to some server that doesn't have many mods (default freeroam server or something like that) and just played on it for a while.
If the crash does not happen, it is definitely a problem with the server you usually spend your time on.