I can also confirm that the problem doesn't occur with linux- image-4.13.0-38-generic_4.13.0-38.43+lp1759920.1_amd64.deb
cat /proc/version_signature => Ubuntu 4.13.0-38.43+lp1759920.1-generic 4.13.16 cat /proc/cmdline => BOOT_IMAGE=/vmlinuz-4.13.0-38-generic root=/dev/mapper/kubuntu--vg-root ro quiet splash vt.handoff=7 dmesg -t | grep -i microcode => microcode: microcode updated early to revision 0x1f, date = 2018-02-07 microcode: sig=0x306a9, pf=0x10, revision=0x1f microcode: Microcode Update Driver: v2.2. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1759920 Title: intel-microcode 3.20180312.0 causes lockup at login screen(w/ linux- image-4.13.0-37-generic) To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/intel-microcode/+bug/1759920/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs