Same issue here, DELL XPS 15 9560, I noticed the error because my Gnome Lock screen clock "stops" at the point when I locked my screen.
Ubuntu 16.04, 4.13.0-26-generic Looking at journalctl, the last message before the clock stopped is "Jan 15 10:21:05 hamide-XPS kernel: [drm:intel_cpu_fifo_underrun_irq_handler [i915]] *ERROR* CPU pipe C FIFO underrun" -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1550779 Title: [i915]] *ERROR* CPU pipe A FIFO underrun - Xorg glitches To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1550779/+subscriptions -- ubuntu-bugs mailing list [email protected] https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
