Steve Bainton: 1) Please post your dmesg of the boot with the latest mainline kernel.
2) >" BIOS not updated, as I would rather not use beta version" The vendor's website gives no indication the latest BIOS is beta. Despite this, as per your https://launchpadlibrarian.net/357032471/CurrentDmesg.txt : ... [ 0.083479] pci 0000:00:00.0: [Firmware Bug]: reg 0x1c: invalid BAR (can't size) ... [ 4.798505] TSC found unstable after boot, most likely due to broken BIOS. Use 'tsc=unstable'. Keeping a broken BIOS version doesn't motivate developers to want to investigate a potential bug in software. 3) >"Ubuntu 14.04 works fine" To clarify, when did you test 14.04 on this hardware, and what kernel version were you using when you tested this? Also, please attach dmesg from a 14.04 test. ** Changed in: xorg (Ubuntu) Status: Confirmed => Incomplete -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1749086 Title: 5 minute delay on booting to login screen To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/xorg/+bug/1749086/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
