I have recently upgraded my system to Debian Jessie (testing) and everything went smoothly, except the occasional distortion when the screen is updating.
When a part of the screen needs to update, lines across the screen appear for several seconds, as if there is some kind of interference. I am using open source driver (for amd 4570) and would really like to get to the bottom of the issue myself, however I am stuck as to what I can actually do next:
Things I have done:
1- rebooted from a live cd to check that the screen and graphics card aren't faulty- all good here, no flicker. 2- changed desktop environments, to rule out some sort of bug. It occurs much less often on XFCE, but it is not eliminated.
3- Updated the system to the latest and installed the latest available kernel (3.16). NO change.
Apart from reinstalling everything from scratch, is there something that I can do?
/var/log/messages, dmesg and kern.long dont indicate any obvious failures.
System is definitely not overheating.