I have been working last years on Ubuntu 14.04 LTS, but in next month there would be end of LTS and I'm looking new distibution for migration. I've already tried several Linux distibutions including Ubuntu 16.04 (Unity)/18.04 (Gnome) and Manjaro XFCE 18.0.4, but on all of them I got some kind of excitation/strain in head and eyes.
I've tried different options for "font hinting" and "antialiasing" but symptoms are same.

Which Linux distributions do you use now (or have used in past without any eye/head/led related problems)?
How did you configure your system and which hardware do you have?
Did you try to switch to modern/recent distributions?

My current configuration:

CPU - i7-7700K 
GPU - AMD HD5450 + with open source drivers (xserver-xorg-video-radeon 1:7.3.0-1ubuntu3.1)
Display - Dell U2711 (CCFL)
Connection - DVI
OS - Ubuntu 14.04, Unity with default options
Kernel - 3.13.0-167-generic X86_64

Linux Mint 19.1 (and prior) have worked ok for me.
When you change distro's, I would mimic the kernel / video drivers and see if that helps

CPU Intel Xeon E3-1285L v4
GPU GeForce GTX 750 Ti | Version 390.116 
Display ViewSonic VA2455sm
Connection DVI
OS Linux MInt 19.1
Kernel 4.15.0-46-generic x86_64
19 days later

@kammerer, I too have similar problems. I still do not understand what the root cause is. But, the following are less problematic for me:

  1. Ubuntu 18.10 (default desktop)
  2. MX Linux (default desktop)
  3. Manjaro KDE (non-free install)
  4. Devuan KDE
  5. PCLinuxOS

Hope one of these will suit you.

I'm finding the latest Mint/Mate much better than ubuntu 18.04.

Linux Mint 19.1 Cinnamon and Lubuntu up to 16.04.4 are the only distros i can use. For Ubuntu / Lubuntu after 16.04.5 LTS i get severe eyestrain in any monitor. Currently i use Mint with no issues with CCFL displays.

21 days later

Actually I tried mostly all of mentioned distros and on all of them I have problem similar to mentioned in first post.

I tried to compare differences in package configurations between Ubuntu 14.04 (which is totally good for me) and other ones. Comparing /var/log/Xorg.0.log I found that depending on xorg version radeon driver uses different acceleration method by default: glamour for new version and EXA for old ones. EXA acceleration by default enables 'SwapbuffersWait' flag (that doesn't work with glamour):

This option controls the behavior of glXSwapBuffers and glXCopySubBufferMESA
calls by GL applications. If enabled, the calls will avoid tearing by making
sure the display scanline is outside of the area to be copied before the copy
occurs. If disabled, no scanline synchronization is performed, meaning tearing
will likely occur. Note that when enabled, this option can adversely affect
the framerate of applications that render frames at less than refresh rate.
.IP
The default value is .B on.

Switching glamour to EXA doesn't work for me, but maybe it would be worth for somebody else.

I also test old Ubuntu versions and found that I can't use even Ubuntu 14.10 (also uses EXA by default).

Maybe it's also worth to share our acceptable and unacceptable configurations. That will help us to find some common patterns:

Good
Ubuntu 14.04, Unity with default options
GPU - AMD HD5450 + with open source drivers (xserver-xorg-video-radeon/radeon 7.3.0)
Kernel - 3.13.0-167-generic X86_64
Mesa - 10.1.3
Xorg server - 1.15.1
Bad
Ubuntu 14.10, Unity with default options
GPU - AMD HD5450 + with open source drivers (xserver-xorg-video-radeon/radeon 7.4.0)
Kernel - 3.16.0-23-generic X86_64
Mesa - 10.3
Xorg server - 1.16
2 months later

@kammerer I assume you tried already the following methods described here?
https://ledstrain.org/d/413-disable-color-dither-method-collection

Currently I run Ubuntu 19.04 with an NVidia card and Nouveau driver connecting to a CCFL display with a VGA cable. This is working pretty well! Also the internal display of the Thinkpad W530 using the descrete NVidia graphics chip with dithering disabled works quite ok.

Is using a different graphics card an option for you?

    deepflame
    Yes, I've tried different options to disable dithering and different ports (DVI, DP, HDMI) on several cards:
    ATI HD5450 and HD6670, Nvidia Quadro P400 and Intel one. But effects are same.

      4 months later

      Myabe it would be helpful for somebody:
      During investigations I've found that Debian 10.1 and especially MX Linux 19 RC (based on Debian 10.1) causes me less discomfort.

      Any idea why they work better?

      dev