GPU HANG: ecode 9:0:0x84dfbffc, in Xorg [1250], reason: Hang on rcs0, action: reset drm/i915: Resetting chip after gpu hang RC6 on

This error message is in syslog when the Desktop freeze before the Display goes black and the login screen came up.

This apparently happens without any apparent connection. Sometimes not for days even though the CPU is 100% full all the time, then again after 20-30 minutes several times in a row.

lsb_release -rd
Description: Ubuntu 16.04.4 LTS
Release: 16.04

mesa 17.2.8-0ubuntu0~16.04.1
libdrm 2.4.83-1~16.04.1

Mar 19 20:12:22 michael-ThinkPad-E470 kernel: [255789.072708] [drm] GPU HANG: ecode 9:0:0x84dfbffc, in Xorg [1250], reason: Hang on rcs0, action: reset
Mar 19 20:12:22 michael-ThinkPad-E470 kernel: [255789.072763] drm/i915: Resetting chip after gpu hang
Mar 19 20:12:22 michael-ThinkPad-E470 kernel: [255789.073059] [drm] RC6 on
Mar 19 20:12:30 michael-ThinkPad-E470 kernel: [255797.047275] drm/i915: Resetting chip after gpu hang
Mar 19 20:12:30 michael-ThinkPad-E470 kernel: [255797.047556] [drm] RC6 on
Mar 19 20:12:43 michael-ThinkPad-E470 kernel: [255810.039289] drm/i915: Resetting chip after gpu hang
Mar 19 20:12:43 michael-ThinkPad-E470 kernel: [255810.039429] [drm] RC6 on
Mar 19 20:12:55 michael-ThinkPad-E470 kernel: [255822.007247] drm/i915: Resetting chip after gpu hang
Mar 19 20:12:55 michael-ThinkPad-E470 kernel: [255822.007407] [drm] RC6 on
Mar 19 20:13:03 michael-ThinkPad-E470 kernel: [255830.071164] drm/i915: Resetting chip after gpu hang
Mar 19 20:13:03 michael-ThinkPad-E470 kernel: [255830.071304] [drm] RC6 on
Mar 19 20:13:25 michael-ThinkPad-E470 gnome-session-binary[31279]: Entering running state