> > Is Debian using nouveau, how to check what driver is being used? > > You can check /var/log/Xorg.0.log > > ok
also I the issue resolved itself, I read on a forum thread that by turning off the power completely will reset the monitor. I think this issue was triggered by using the monitor on two different systems alternatively. I think one of the laptops had it running at 75Hz Any way I am glad that it's resolved. -- Kind regards, Yudi