The video mode used in login screen and in the desktop environment was bad: it was 1600x1200, but somewhat shaky. My fix was to add this in Section "Screen" of /etc/X11/xorg.conf:
DefaultDepth 24 SubSection "Display" Depth 24 Virtual 1280 960 EndSubSection
And then reboot (or restart X by Ctrl-Alt-Backspace in login screen).
It is old Matrox G100 in the computer, direct rendering does not work here btw.
The video mode used in login screen and in the desktop environment was bad: it was 1600x1200, but somewhat shaky.
My fix was to add this in Section "Screen" of /etc/X11/xorg.conf:
DefaultDepth 24
EndSubSection
SubSection "Display"
Depth 24
Virtual 1280 960
And then reboot (or restart X by Ctrl-Alt-Backspace in login screen).
It is old Matrox G100 in the computer, direct rendering does not work here btw.