https://bugs.freedesktop.org/show_bug.cgi?id=41418
--- Comment #6 from Franz Brauße dev@karlchenofhell.org 2011-10-05 11:40:51 PDT --- Created an attachment (id=52020) --> (https://bugs.freedesktop.org/attachment.cgi?id=52020) xrandr --verbose with several 'scaling mode' properties
Appearently the scaling mode property was set to "Full" by default.
There is no difference in the visible image between "Full" and "Full aspect" scaling mode, "Center" does enable the backlight but the screen stays black, "None" shows the FB at coords (0,0) and a cloned portion of it below separated by a black horizontal bar as the native display resolution of 1600x1200 is used (so I'd say that one works).
I've attached xrandr --verbose outputs for "Full", "None" and the non-working "Center" scaling modes using 1400x1050 resolution. If those outputs for 1440x900 would help, too, I'll upload them as well.
Thank you for taking a look at this issue.