FWIW, I've switched back to Chromium after installing 16.04 on the same machine, to see if I can reproduce it with the Xenial kernel, and it's been 4 days without any such lockups.
-- You received this bug notification because you are a member of Ubuntu-X, which is subscribed to xserver-xorg-video-intel in Ubuntu. https://bugs.launchpad.net/bugs/1451632 Title: drm:intel_cpu_fifo_underrun_irq_handler [i915] - complete lockups To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/xserver-xorg-video-intel/+bug/1451632/+subscriptions _______________________________________________ Mailing list: https://launchpad.net/~ubuntu-x-swat Post to : ubuntu-x-swat@lists.launchpad.net Unsubscribe : https://launchpad.net/~ubuntu-x-swat More help : https://help.launchpad.net/ListHelp