Be sure to enable ‘Above 4G Decoding’ and ‘Resizazble BAR Support’ in the BIOS of your PC!
WoW really cares about that (as of last week) for some reason. I was getting constant crashes when starting WoW from the Battle.Net launcher, until I made those changes (Fedora/KDE Linux, Proton Steam Experimental (and other non-Steam Protons)).
Irony is that I had them set before in by BIOS, but had updated by BIOS and assumed my non-default settings would carry over to the new BIOS version, but did not. So double-check your BIOS for those two settings, if you are having problems.
I can only speak towards Retail. I haven’t tried Classic.
I went back and updated the title to state ‘Retail’.
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