I am having the same issue, reverting to 5.3.0-51 resolves the problem for me. I am on an Intel 5930k CPU on an X99 motherboard however. Running the apport-collect command suggested above did not collect or send further details to this bug because I am not the original creator.
-- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1880041 Title: Failing to shutdown/power off or reboot on AMD Ryzen CPUs on kernel versions 5.3.0-52 and later To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux-meta-hwe/+bug/1880041/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs