Thierry de Coulon composed on 2017-08-28 12:53 (UTC+0200): > I have a laptop (Thinkpad X220t) freshly reinstalled with latest openSuSE (I > did not yet have time to check under other distributions). > I installed Trinity over Gnome 3; If I boot and start Trinity (first user) I > have nothing on the external screen (which is a beamer, 1024x768). Internal > screen is at 1366*900. 1366x900 is a seriously uncommon resolution. I wonder if Gnome, Xorg or driver devs even know it exists? Does xrandr -q confirm it's what you have? According to https://www.notebookcheck.net/Review-Lenovo-ThinkPad-X220T-4298-2YG-Convertible-Notebook.60217.0.html that model only comes with 1366x768 screens. > If I start a second user (under Gnome) the internal screen resizes to 1024x768 > and I get an image on the beamer. Gnome is very demanding compared to other DEs. If GDM is still installed, removing it might help. Make sure to configure trinity-tdm as your display manager. I have lots of openSUSE installations with KDE3 or TDE, none on laptops, but several with dual displays available. None have ever done as you describe, and GDM is never installed. -- "The wise are known for their understanding, and pleasant words are persuasive." Proverbs 16:21 (New Living Translation) Team OS/2 ** Reg. Linux User #211409 ** a11y rocks! Felix Miata *** http://fm.no-ip.com/