I don't have these problems with Windows on the device, either.
I really hope a fix gets implemented. Thank you.

On Tue, Apr 2, 2019, 10:45 PM Daniel van Vugt <daniel.van.v...@canonical.com>
wrote:

> Thanks for the animation.
>
> I think that flicker is occurring in the LCD itself. The reason is that
> the old gradient (which was only used in Ubuntu 18.10) covers more
> colours than 24-bit RGB can support. On top of that, if your monitor is
> only 18-bit RGB in hardware then you will see even fewer colours and the
> display/kernel will flicker on purpose to create the illusion of all the
> shades it can't really display. This is called temporal dithering, or
> Frame Rate Control:
>
>   https://en.wikipedia.org/wiki/Frame_rate_control
>
> Essentially that gradient is just a pathological case which will make
> the shimmering/flickering more visible than it usually is. For this and
> other reasons, I reported a bug 1789355 too.
>
> In the end this is a hardware limitation. But it is a common one which
> the kernel driver should have some control over. You should be able to
> configure the nouveau kernel driver directly using something like:
>
>   xrandr --output DVI-I-1 --set "dithering mode" "off"
>
> or
>
>   xrandr --output DVI-I-1 --set "dithering mode" "static 2x2"
>
> based on your Xrandr.txt which says:
>
>         dithering depth: auto
>                 supported: auto, 6 bpc, 8 bpc
>         dithering mode: auto
>                 supported: auto, off, static 2x2, dynamic 2x2
>
> I am going to reassign this bug to the kernel because it sounds like the
> only software solution possible here would be for the kernel to
> automatically choose a less annoying dithering mode for this model of
> monitor.
>
> P.S. The gradient is completely gone in Ubuntu 19.04 so you won't have
> any trouble there.
>
>
> ** Package changed: xorg-server (Ubuntu) => linux (Ubuntu)
>
> --
> You received this bug notification because you are subscribed to the bug
> report.
> https://bugs.launchpad.net/bugs/1819023
>
> Title:
>   [nouveau] Scrolling screen flicker, especially on default Ubuntu lock
>   screen
>
> Status in linux package in Ubuntu:
>   Confirmed
>
> Bug description:
>   My screen is experiencing a weird "scrolling" flicker, especially
>   while displaying blue, indigo, and violet hues/colors, such as on the
>   default Ubuntu 18.10 (x64 Desktop) lock screen. The screen flicker
>   scrolls up and down, with the brightest part of the flicker being
>   towards the top, with a gradient that fades back to the original color
>   near the bottom.
>
>   Problem occurs on any one monitor on any one video output protocol
>   (DVI-D, HDMI, and VGA).
>
>
>   I will upload an illustration or render as soon as possible for better
> explanation.
>
>   ProblemType: Bug
>   DistroRelease: Ubuntu 18.10
>   Package: xorg 1:7.7+19ubuntu8
>   ProcVersionSignature: Ubuntu 4.18.0-16.17-generic 4.18.20
>   Uname: Linux 4.18.0-16-generic x86_64
>   ApportVersion: 2.20.10-0ubuntu13.2
>   Architecture: amd64
>   BootLog: Error: [Errno 13] Permission denied: '/var/log/boot.log'
>   CompositorRunning: None
>   CurrentDesktop: ubuntu:GNOME
>   Date: Thu Mar  7 10:39:50 2019
>   DistUpgraded: 2018-10-19 10:50:54,557 ERROR got error from
> PostInstallScript ./xorg_fix_proprietary.py (g-exec-error-quark: Failed to
> execute child process “./xorg_fix_proprietary.py” (No such file or
> directory) (8))
>   DistroCodename: cosmic
>   DistroVariant: ubuntu
>   ExtraDebuggingInterest: Yes, if not too technical
>   GraphicsCard:
>    NVIDIA Corporation GF108 [GeForce GT 440] [10de:0de0] (rev a1) (prog-if
> 00 [VGA controller])
>      Subsystem: NVIDIA Corporation GF108 [GeForce GT 440] [10de:0828]
>   InstallationDate: Installed on 2018-08-17 (202 days ago)
>   InstallationMedia: Ubuntu 18.04 LTS "Bionic Beaver" - Release amd64
> (20180426)
>   MachineType: BIOSTAR Group A880G+
>   ProcEnviron:
>    PATH=(custom, no user)
>    XDG_RUNTIME_DIR=<set>
>    LANG=en_US.UTF-8
>    SHELL=/bin/bash
>   ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-4.18.0-16-generic
> root=UUID=a967adb1-1600-455b-8704-e2bf5de5081d ro quiet splash vt.handoff=1
>   SourcePackage: xorg
>   UpgradeStatus: Upgraded to cosmic on 2018-10-19 (139 days ago)
>   dmi.bios.date: 09/21/2011
>   dmi.bios.vendor: American Megatrends Inc.
>   dmi.bios.version: 080016
>   dmi.board.asset.tag: To Be Filled By O.E.M.
>   dmi.board.name: A880G+
>   dmi.board.vendor: BIOSTAR Group
>   dmi.chassis.asset.tag: None
>   dmi.chassis.type: 3
>   dmi.chassis.vendor: BIOSTAR Group
>   dmi.modalias:
> dmi:bvnAmericanMegatrendsInc.:bvr080016:bd09/21/2011:svnBIOSTARGroup:pnA880G+:pvr:rvnBIOSTARGroup:rnA880G+:rvr:cvnBIOSTARGroup:ct3:cvr:
>   dmi.product.family: To Be Filled By O.E.M.
>   dmi.product.name: A880G+
>   dmi.product.sku: To Be Filled By O.E.M.
>   dmi.sys.vendor: BIOSTAR Group
>   version.compiz: compiz N/A
>   version.libdrm2: libdrm2 2.4.95-1
>   version.libgl1-mesa-dri: libgl1-mesa-dri 18.2.2-0ubuntu1
>   version.libgl1-mesa-glx: libgl1-mesa-glx 18.2.2-0ubuntu1
>   version.xserver-xorg-core: xserver-xorg-core 2:1.20.1-3ubuntu2.1
>   version.xserver-xorg-input-evdev: xserver-xorg-input-evdev N/A
>   version.xserver-xorg-video-ati: xserver-xorg-video-ati 1:18.1.0-1
>   version.xserver-xorg-video-intel: xserver-xorg-video-intel
> 2:2.99.917+git20171229-1ubuntu1
>   version.xserver-xorg-video-nouveau: xserver-xorg-video-nouveau 1:1.0.15-3
>
> To manage notifications about this bug go to:
> https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1819023/+subscriptions
>

-- 
You received this bug notification because you are a member of Kernel
Packages, which is subscribed to linux in Ubuntu.
https://bugs.launchpad.net/bugs/1819023

Title:
  [nouveau] Scrolling screen flicker, especially on default Ubuntu lock
  screen

Status in linux package in Ubuntu:
  Confirmed

Bug description:
  My screen is experiencing a weird "scrolling" flicker, especially
  while displaying blue, indigo, and violet hues/colors, such as on the
  default Ubuntu 18.10 (x64 Desktop) lock screen. The screen flicker
  scrolls up and down, with the brightest part of the flicker being
  towards the top, with a gradient that fades back to the original color
  near the bottom.

  Problem occurs on any one monitor on any one video output protocol
  (DVI-D, HDMI, and VGA).

  
  I will upload an illustration or render as soon as possible for better 
explanation.

  ProblemType: Bug
  DistroRelease: Ubuntu 18.10
  Package: xorg 1:7.7+19ubuntu8
  ProcVersionSignature: Ubuntu 4.18.0-16.17-generic 4.18.20
  Uname: Linux 4.18.0-16-generic x86_64
  ApportVersion: 2.20.10-0ubuntu13.2
  Architecture: amd64
  BootLog: Error: [Errno 13] Permission denied: '/var/log/boot.log'
  CompositorRunning: None
  CurrentDesktop: ubuntu:GNOME
  Date: Thu Mar  7 10:39:50 2019
  DistUpgraded: 2018-10-19 10:50:54,557 ERROR got error from PostInstallScript 
./xorg_fix_proprietary.py (g-exec-error-quark: Failed to execute child process 
“./xorg_fix_proprietary.py” (No such file or directory) (8))
  DistroCodename: cosmic
  DistroVariant: ubuntu
  ExtraDebuggingInterest: Yes, if not too technical
  GraphicsCard:
   NVIDIA Corporation GF108 [GeForce GT 440] [10de:0de0] (rev a1) (prog-if 00 
[VGA controller])
     Subsystem: NVIDIA Corporation GF108 [GeForce GT 440] [10de:0828]
  InstallationDate: Installed on 2018-08-17 (202 days ago)
  InstallationMedia: Ubuntu 18.04 LTS "Bionic Beaver" - Release amd64 (20180426)
  MachineType: BIOSTAR Group A880G+
  ProcEnviron:
   PATH=(custom, no user)
   XDG_RUNTIME_DIR=<set>
   LANG=en_US.UTF-8
   SHELL=/bin/bash
  ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-4.18.0-16-generic 
root=UUID=a967adb1-1600-455b-8704-e2bf5de5081d ro quiet splash vt.handoff=1
  SourcePackage: xorg
  UpgradeStatus: Upgraded to cosmic on 2018-10-19 (139 days ago)
  dmi.bios.date: 09/21/2011
  dmi.bios.vendor: American Megatrends Inc.
  dmi.bios.version: 080016
  dmi.board.asset.tag: To Be Filled By O.E.M.
  dmi.board.name: A880G+
  dmi.board.vendor: BIOSTAR Group
  dmi.chassis.asset.tag: None
  dmi.chassis.type: 3
  dmi.chassis.vendor: BIOSTAR Group
  dmi.modalias: 
dmi:bvnAmericanMegatrendsInc.:bvr080016:bd09/21/2011:svnBIOSTARGroup:pnA880G+:pvr:rvnBIOSTARGroup:rnA880G+:rvr:cvnBIOSTARGroup:ct3:cvr:
  dmi.product.family: To Be Filled By O.E.M.
  dmi.product.name: A880G+
  dmi.product.sku: To Be Filled By O.E.M.
  dmi.sys.vendor: BIOSTAR Group
  version.compiz: compiz N/A
  version.libdrm2: libdrm2 2.4.95-1
  version.libgl1-mesa-dri: libgl1-mesa-dri 18.2.2-0ubuntu1
  version.libgl1-mesa-glx: libgl1-mesa-glx 18.2.2-0ubuntu1
  version.xserver-xorg-core: xserver-xorg-core 2:1.20.1-3ubuntu2.1
  version.xserver-xorg-input-evdev: xserver-xorg-input-evdev N/A
  version.xserver-xorg-video-ati: xserver-xorg-video-ati 1:18.1.0-1
  version.xserver-xorg-video-intel: xserver-xorg-video-intel 
2:2.99.917+git20171229-1ubuntu1
  version.xserver-xorg-video-nouveau: xserver-xorg-video-nouveau 1:1.0.15-3

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https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1819023/+subscriptions

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