Use latest AMd wip kernel, firmware files and Oibaf ppa. https://cgit.freedesktop.org/~agd5f/linux/log/?h=drm-next-4.21-wip https://git.kernel.org/pub/scm/linux/kernel/git/firmware/linux-firmware.git/log/amdgpu https://launchpad.net/~oibaf/+archive/ubuntu/graphics-drivers