I noticed the same problems and a few more. For example closing the lid hangs the system. Disconnecting the power supply hangs the system. All clearly kernel related.
I tried the iommu=soft solution which didn't work for me. Also adding amd_iommu=pt didn't help. The best fix I found so far was upgrading to a more recent kernel. i.e. Get this script: https://github.com/pimlie/ubuntu-mainline-kernel.sh And install the latest kernel. -- You received this bug notification because you are a member of Ubuntu-X, which is subscribed to xserver-xorg-video-amdgpu in Ubuntu. https://bugs.launchpad.net/bugs/1872452 Title: [amdgpu] Boot into black screen without power supply (Kubuntu on AMD) To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/kwin/+bug/1872452/+subscriptions _______________________________________________ Mailing list: https://launchpad.net/~ubuntu-x-swat Post to : ubuntu-x-swat@lists.launchpad.net Unsubscribe : https://launchpad.net/~ubuntu-x-swat More help : https://help.launchpad.net/ListHelp
