[Bug 108514] heavy screen flickering with Mobility Radeon X1600 and kernel version onwards 3.13

https://bugs.freedesktop.org/show_bug.cgi?id=108514

--- Comment #4 from Werner Lueckel werner.lueckel@googlemail.com --- - I attached 2 dmesg-listings; booting Ubuntu14.04, Kernel3.13 -> screen is o.k.; no flickering booting Ubuntu18.04, Kernel4.15 -> screen flickers. - no Xorg log since the flickering happens already in text-mode - I did the following test (on Ubuntu18.04): . boot with radeon.modeset=0 (thus: disable radeon driver) -> screen o.k.; NO flickering . then sudo modprobe -v radeon modeset=1 -> and the flickering starts ...