Package: src:linux Version: 4.17~rc3-1~exp1 Severity: normal My laptop has a resolution of 1920x1080. xrandr -s 800x600 results in a black screen. Using KDE, I can leave the session by typing ctrl-alt-delete while the screen is black. A resolution of 1360x768 is working. /sys/kernel/debug/dri/0/framebuffer contains: framebuffer[82]: allocated by = Xorg refcount=1 format=XR24 little-endian (0x34325258) modifier=0x100000000000001 size=800x600 layers: size[0]=800x600 pitch[0]=3584 offset[0]=0 obj[0]:(null)