Weird screen flickering issue in ubuntu 17.04 GNOME

I have the same problem with the display flickering after updating to 17.04 and 17.10. My graphics hardware (Unity->Details)

 Intel HD Graphics 620 (Kabylake GT2)

I assume you have a 4K display. Check Unity->Displays and if you see 3840x2160, that means your equipment supports 4K. If the flickering becomes annoying, a temporary workaround is to reduce your display resolution to 2048x1536. You should probably set the scale to a suitable font size. Note that as a result of changing the resolution, your display aspect ratio will show a smaller output but it's a lot easier to look at than a flickering screen.

Intel provides a nice GUI-based graphics update tool. However, the tool currently doesn't support 17.04+ since it's a relatively recent Ubuntu release.

Here's the link to the Intel Graphics update tool for your future reference so that you can keep an eye out for when 17.04+ driver support becomes available.

https://01.org/linuxgraphics/downloads/intel-graphics-update-tool-linux-os-v2.0.2

Hope this helps.

I just put together a new system with an i5-8600 CPU and 4K monitor and had similar issues with Kubuntu 17.10 installed. Here's what I tried to solve them ...

1. Add i915.alpha_support=1 to the boot parameters (kernel parameters) by editing /etc/default/grub.

   Change

    GRUB_CMDLINE_LINUX_DEFAULT="quiet splash"
   

   to

    GRUB_CMDLINE_LINUX_DEFAULT="quiet splash i915.alpha_support=1"
   

   This allowed be to get 4K output (previously only FHD) but there were some really strange display issues. Looked like problems with frame buffer switching.

2. Installed the graphic packages from Oibaf's PPA repository:

   This improved the situation greatly but there were still a few flashes.

   Unfortunately, a few days ago there was an update to the repository and, after running sudo apt update && apt upgrade I was greeted by a blank white screen and no mouse or keyboard at the next reboot!

3. Reverted to standard Ubuntu drivers ...

    sudo apt-get install ppa-purge
    sudo ppa-purge ppa:oibaf/graphics-drivers
   

4. Downloaded and installed the INTEL GRAPHICS UPDATE TOOL FOR LINUX* OS V2.0.6 from

   https://01.org/linuxgraphics/downloads/intel-graphics-update-tool-linux-os-v2.0.6

   Follow the installation instructions on this page. In particular don't forget the "SIGNATURES - UBUNTU*" section.

   BUT, Don't run the updater yet!

   This version is intended for Ubuntu 17.04, but, with a little messing about, seems to work fine on 17.10.

   You need to, temporarily, lie to the Update Tool about what release you are running. You do this by changing the contents of /etc/lsb-release.

   Backup the file first

    sudo cp /etc/lsb-release /etc/lsb-release.backup
   

   Then replace the contents of /etc/lsb-release with

    DISTRIB_ID=Ubuntu
    DISTRIB_RELEASE=17.04
    DISTRIB_CODENAME=zesty
    DISTRIB_DESCRIPTION="Ubuntu 17.04"
   

   Then run the Update Tool like this

    intel-graphics-update-tool
   

   or from the Application Launcher > Settings menu.

   Finally reinstate the original /etc/lsb-release.

    sudo mv /etc/lsb-release.backup /etc/lsb-release
   

I have not seen any display glitches since running the Update Tool. I have had a number of crashes of the kdenlive video editor but I can't really tell if they are related to the graphics drivers or not.

Hope this info helps.