Hardwiring the video modes fixed it again: Currently my cmdline isBOOT_IMAGE=/vmlinuz-3.11-trunk-amd64 root=/dev/mapper/S830--512A-root ro video=DP-1:2560x1440-24@60e video=DP-2:2560x1440-24@60e video=DVI-0:2560x1440-24@60e drm.debug=4 log_buf_len=10M sysrq_always_enabled Some time in the past, when I started to use radeonsi, I needed to do that too, but not for some time.