I appear to have the same problem with my Dell Optiplex desktop machine and my Dell XPS 13 Developer Edition. The XPS is brand new and has been updated to the latest BIOS version. The Optiplex has a somewhat aged BIOS, but I've never seen any problems until now.
Both machines have been updated by doing a clean install of 16.04; Kubuntu on this machine and Ubuntu on the XPS. One thing that I've discovered is that the machine can be pinged when it's down, but otherwise the symptoms are identical to those reported above. Entering coredumpctl returns 'No coredumps found'. The problem has been observed when I am typing, moving the mouse, reading text or simply doing nothing. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1575467 Title: Ubuntu 16.04 consistently freezes up / hangs To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1575467/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
