I'm using UX21A Asus Zenbook Prime.
When I connected HDMI socket to an external display and turn on the laptop, Ubuntu didn't show build in display even it said display was recognized and activated. It happened on Ubuntu 16.04 and Linux Mint 18 Mint even when they were started as Live USB booting.
When I switched off the build in display and reactivate it through Display Setting GUI, it started showing. But with xrandr command, it didn't.
I unplugged HDMI and turn on the laptop and plug HDMI again after confirmed the BIOS Logo, the problem didn't show up.
The situation I confirmed on several environment were all the same.
It suppose to be caused by a problem which the laptop considers the external display as primary one.
So currently, I unplug the HDMI when I start it up.
I also asked in askubuntu.com but it doesn't seem I could get the feedback. This is my first bug repport and please be kind.
sudo lspci -vnvn > lspci-vnvn.log
returns
Ubuntu 4.4.0-38.57-generic 4.4.19
---
ApportVersion: 2.20.1-0ubuntu2.1
Architecture: amd64
AudioDevicesInUse:
USER PID ACCESS COMMAND
/dev/snd/controlC0: zenbook 1475 F.... pulseaudio
CurrentDesktop: X-Cinnamon
DistroRelease: Ubuntu 16.04
HibernationDevice: RESUME=UUID=51f4543d-f960-4aea-8840-72631c112329
InstallationDate: Installed on 2016-10-05 (4 days ago)
InstallationMedia: Ubuntu 16.04 LTS "Xenial Xerus" - Release amd64(20160426.1)
MachineType: ASUSTeK COMPUTER INC. UX21A
Package: linux (not installed)
ProcFB: 0 inteldrmfb
ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-4.4.0-38-generic.efi.signed root=UUID=cce15b3a-8ba8-40d2-a621-c8b542bb3484 ro quiet splash vt.handoff=7
ProcVersionSignature: Ubuntu 4.4.0-38.57-generic 4.4.19
RelatedPackageVersions:
linux-restricted-modules-4.4.0-38-generic N/A
linux-backports-modules-4.4.0-38-generic N/A
linux-firmware 1.157.3
Tags: xenial
Uname: Linux 4.4.0-38-generic x86_64
UpgradeStatus: No upgrade log present (probably fresh install)
UserGroups: adm cdrom dip lpadmin plugdev sambashare sudo
_MarkForUpload: True
dmi.bios.date: 11/14/2012
dmi.bios.vendor: American Megatrends Inc.
dmi.bios.version: UX21A.216
dmi.board.asset.tag: ATN12345678901234567
dmi.board.name: UX21A
dmi.board.vendor: ASUSTeK COMPUTER INC.
dmi.board.version: 1.0
dmi.chassis.asset.tag: No Asset Tag
dmi.chassis.type: 10
dmi.chassis.vendor: ASUSTeK COMPUTER INC.
dmi.chassis.version: 1.0
dmi.modalias: dmi:bvnAmericanMegatrendsInc.:bvrUX21A.216:bd11/14/2012:svnASUSTeKCOMPUTERINC.:pnUX21A:pvr1.0:rvnASUSTeKCOMPUTERINC.:rnUX21A:rvr1.0:cvnASUSTeKCOMPUTERINC.:ct10:cvr1.0:
dmi.product.name: UX21A
dmi.product.version: 1.0
dmi.sys.vendor: ASUSTeK COMPUTER INC.
This bug is missing log files that will aid in diagnosing the problem. From a terminal window please run:
apport-collect 1631678
and then change the status of the bug to 'Confirmed'.
If, due to the nature of the issue you have encountered, you are unable to run this command, please add a comment stating that fact and change the bug status to 'Confirmed'.
This change has been made by an automated script, maintained by the Ubuntu Kernel Team.