[ASUS GL552VW] Loss of signal (black screen) on external monitor

[Andrii Beznosiuk]

External screen flickers on and off (image is present and then signal is lost, flickering is random, but very often, ~3 times in 10 seconds) on a fresh installation.
Details:
- I'm using a laptop (ASUS GL552VW) with external monitor connected via HDMI. The HDMI port is connected to my iGPU, Intel HD 530 (there is no way to make that HDMI work with NVIDIA GTX 960M in my laptop).
- Nothing was installed after installing the OS - i connected to the Internet while installing the system and marked the option to download the updates.
- I had that issue on Windows 10 - I fixed it by installing a latest Intel GPU driver from laptop manufacturer's (ASUS) site, uninstalling drivers installed by Windows - they were the latest Intel drivers.
- Internal screen works fine.
- If I mirror external and internal monitor, external isn't flickering, but internal monitor's resolution is lower that external's one.

ProblemType: Bug
DistroRelease: Ubuntu 22.04
Package: xorg 1:7.7+23ubuntu2
ProcVersionSignature: Ubuntu 5.15.0-33.34-generic 5.15.30
Uname: Linux 5.15.0-33-generic x86_64
ApportVersion: 2.20.11-0ubuntu82
Architecture: amd64
BootLog: Error: [Errno 13] Permission denied: '/var/log/boot.log'
CasperMD5CheckResult: pass
CompositorRunning: None
CurrentDesktop: ubuntu:GNOME
Date: Thu May 26 22:34:16 2022
DistUpgraded: Fresh install
DistroCodename: jammy
DistroVariant: ubuntu
ExtraDebuggingInterest: Yes
GraphicsCard:
 Intel Corporation HD Graphics 530 [8086:191b] (rev 06) (prog-if 00 [VGA controller])
   Subsystem: ASUSTeK Computer Inc. HD Graphics 530 [1043:1c5d]
   Subsystem: ASUSTeK Computer Inc. GM107M [GeForce GTX 960M] [1043:1c5d]
InstallationDate: Installed on 2022-05-26 (0 days ago)
InstallationMedia: Ubuntu 22.04 LTS "Jammy Jellyfish" - Release amd64 (20220419)
MachineType: ASUSTeK COMPUTER INC. GL552VW
ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-5.15.0-33-generic root=UUID=be9d6e78-64ad-42f3-883b-15903e52b776 ro quiet splash vt.handoff=7
SourcePackage: xorg
Symptom: display
UpgradeStatus: No upgrade log present (probably fresh install)
dmi.bios.date: 04/25/2019
dmi.bios.release: 5.11
dmi.bios.vendor: American Megatrends Inc.
dmi.bios.version: GL552VW.304
dmi.board.asset.tag: ATN12345678901234567
dmi.board.name: GL552VW
dmi.board.vendor: ASUSTeK COMPUTER INC.
dmi.board.version: 1.0
dmi.chassis.asset.tag: ATN12345678901234567
dmi.chassis.type: 10
dmi.chassis.vendor: ASUSTeK COMPUTER INC.
dmi.chassis.version: 1.0
dmi.modalias: dmi:bvnAmericanMegatrendsInc.:bvrGL552VW.304:bd04/25/2019:br5.11:svnASUSTeKCOMPUTERINC.:pnGL552VW:pvr1.0:rvnASUSTeKCOMPUTERINC.:rnGL552VW:rvr1.0:cvnASUSTeKCOMPUTERINC.:ct10:cvr1.0:skuASUS-NotebookSKU:
dmi.product.family: GL
dmi.product.name: GL552VW
dmi.product.sku: ASUS-NotebookSKU
dmi.product.version: 1.0
dmi.sys.vendor: ASUSTeK COMPUTER INC.
version.compiz: compiz N/A
version.libdrm2: libdrm2 2.4.110-1ubuntu1
version.libgl1-mesa-dri: libgl1-mesa-dri 22.0.1-1ubuntu2
version.libgl1-mesa-glx: libgl1-mesa-glx N/A
version.xserver-xorg-core: xserver-xorg-core 2:21.1.3-2ubuntu2
version.xserver-xorg-input-evdev: xserver-xorg-input-evdev N/A
version.xserver-xorg-video-ati: xserver-xorg-video-ati 1:19.1.0-2build3
version.xserver-xorg-video-intel: xserver-xorg-video-intel 2:2.99.917+git20210115-1
version.xserver-xorg-video-nouveau: xserver-xorg-video-nouveau 1:1.0.17-2build1

[Daniel van Vugt (vanvugt)]

Thanks for the bug report.

While the flickering is happening please run:

  journalctl -b0 > journalwithflicker.txt

and attach the resulting text file here.

Next please try selecting 'Ubuntu on Xorg' on the login screen, login and run:

  journalctl -b0 > journalwithxorg.txt
  xrandr --verbose > xrandr.txt

and attach the resulting text files here.

[Andrii Beznosiuk (hiresu)]

Thank you for quick response! Here are those files.

[Daniel van Vugt (vanvugt)]

Thanks. I don't see anything relevant in those logs.

Next please:

1. Tell us if logging into 'Ubuntu on Xorg' fixes the flicker.

2. Attach a video of the problem.

3. Try the workaround mentioned in bug 1958191.

4. Try a different HDMI cable if you can find one, in case it's just below spec for 1080p + 60Hz + whatever colour depth the kernel is using. Such problems may manifest in Linux but not in Windows due to signalling differences.

[Andrii Beznosiuk (hiresu)]

Thanks, Daniel.

1. Logging into Ubuntu on Xorg didn't fix the issue.

2. I will attach it in the next message.

3. I tried those workarounds and found no luck. (parameters are visible while editing config in grub before loading)

4. I tried 2 other cables and issue persisted.

[Daniel van Vugt (vanvugt)]

Without mirroring, please try reducing the resolution of the external monitor. Does that stop the flicker?

[Daniel van Vugt (vanvugt)]

Please also try this in a Xorg session:

  xrandr --output HDMI-2 --set "max bpc" 8

If that fixes the problem then you should subscribe to https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/2412

[Daniel van Vugt (vanvugt)]

See also bug 1929209

[Andrii Beznosiuk (hiresu)]

1. Yes, reducing resolution of the external monitor (1440 x 900, to be exact) fixed the issue.
2. I typed that in the terminal and issue persisted.
3. Unfortunately, my laptop doesn't support USB-C DisplayPort (i've tried with my friend's 2K monitor with DisplayPort to USB-C cable and the monitor wasn't receiving any signal), and changing refresh rate to bearable numbers (like 50Hz) didn't help.

[Daniel van Vugt (vanvugt)]

Please also follow the instructions in comment #10, remembering to log into 'Ubuntu on Xorg' first. I'm hoping that will allow you to maintain a stable 1920x1080 60Hz signal.

[Daniel van Vugt (vanvugt)]

Or even try:

  xrandr --output HDMI-2 --set "max bpc" 6

[Andrii Beznosiuk (hiresu)]

Sorry, I forgot to add that I did all of those actions in Xorg session. Xrandr wouldn't let me change output settings If I was in Wayland session.
Unfortunately, changing max bpc to 6 under Xorg session didn't give an effect - screen is still flickering, although not so violently. I tried to change it to lower numbers, such as 3, but no luck either.

[Daniel van Vugt (vanvugt)]

Sorry my mistake. The minimum value of "max bpc" for your HDMI-2 is 8, as mentioned in the attachment in comment #4. Please use that in a Xorg session and tell us if that solves the problem at 1920x1080:

  xrandr --output HDMI-2 --set "max bpc" 8

Although you can't change the setting in a Wayland session, you can change it in Xorg and then log out and into a Wayland session and the kernel should remember the same setting.

A proper solution is coming in:
https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/2412

[Andrii Beznosiuk (hiresu)]

Setting "max bpc" to 8 didn't solve the problem, unfortunately.