No need to throw away those cards. They are serviceable. The Centos forum proposes /etc/X11/xorg.conf.d/20-radeon.conf. An apparently stable workaround for this bug as observed on my 20.04.1 system with inexpensive Dell Radeon graphics card.
Was something forgotten along the way as basic Radeon driver installation setting rules were propagated? These cards were working in 18.04... According to post https://forums.centos.org/viewtopic.php?t=72792 the following option is most relevant to setting a stable acceleration mode remedially for the ring 0 freeze deadline kernel errors: Option "AccelMethod" "exa" -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1707695 Title: radeon 0000:03:00.0: ring 0 stalled for more than 10000msec To manage notifications about this bug go to: https://bugs.launchpad.net/linux/+bug/1707695/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs