A while back my work replaced my laptop with an HP EliteBook 850 G6 with Windows 10 1909 (18363.1316) and Intel UHD 620 graphics. Immediately I noticed that my eyes were struggling to focus and I started getting severe strain and headaches, even using external monitors that I've been otherwise comfortably using for years.

I began researching and seeking solutions (this is when I found ledstrain, Thanks! 😄) and somewhere stumbled on external graphics or eGFX or eGPU. I found that my laptop did indeed have a Thunderbolt port and so I ordered this egfx chassis: https://www.sonnettech.com/product/egfx-breakaway-box/overview.html

I threw a GeForce GT610 card into it and hooked it up to my laptop. I've now been working on this setup for a week and a half and I'm happy to report that much (not all) of my eyestrain and headaches are gone.

After installing the card, my fisrt attempt at installing drivers was with version 353.62, but I couldn't get them to install. I made a second attempt with Nvidia drivers version 391.35 and they installed right away.

I don't consider this machine completely solved by a longshot, but this experience I think provides two very key takeaways for all of us:

1. eGFX opens up (most of) the world of desktop graphics cards for us to use with laptops.
If you have a Thunderbolt port on your laptop, you can plug in an eGFX chassis and make use of desktop graphics cards on your laptop. This particular one that I am using has a list of compatible cards. For Nvidia cards, it only goes back as far as the 1000 series. BUT, their main concern when discussing compatibility seems to be power consumption, so I assumed older cards would work as well as they tend to draw less power than newer cards. Sure enough, my GT610 works in it just fine. I assume that most, if not all, of the 600 series Nvidia cards will work in it. I plan to try more.

2. I BELIEVE that I am completely bypassing the onboard Intel integrated graphics on this laptop now.
I have the chassis connected to my laptop via Thunderbolt and then my external monitors connected directly to the GT610 card. Right away I noticed that the color feels more "flat" like many have described on this site. It still weirds out my eyes a little and I find that the focusing issue still seems to be there, but largely (not completely) without the pain I was experiencing previously. I think that Win10 and Intel620 together introduced a number of different things that bug my eyes and routing through this external card resolved some of them, but the ones coming from Windows are still there.

The next steps I have planned for this machine are:

  1. Confirm with more confidence that I am completely bypassing the onboard Intel integrated graphics
  2. Update to Win10 2004/20H2 in hopes that it becomes even more comfortable. If that doesn't work, I plan to roll it all the way back to 2015 LTSB.
  3. Try different versions of Nvidia drivers. Currently I have version 391.35.
  4. Try different cards in it. I do notice that my window animations are a bit choppy with the GT610, I'm hoping that's easily solved with a beefier card like a GTX650. This isn't really that important to me, I only vaguely notice that it happens but it doesn't bother me at all. It would on my own computer, but not on one that work provides me just for work. If this proves unsolvable I'll consider it a small price to pay for more comfortable viewing.

One thing I would love input from this community on: Are there versions of Nvidia drivers that you are finding more comfortable than others?

    That's really interesting!

    I've done a lot of testing (with a capture card & image analysis, not by eye) on intel graphics and never found them to use temporal dithering - though a lot of people believe they do use temporal dithering and that is why intel graphics causes them discomfort. Based on my testing, I think intel is uncomfortable because it does not use temporal dithering. See, LCDs flicker at half their framerate due to LCD inversion. I think having a broadband flicker from temporal dithering breaks up that half frame rate flicker from inversion and makes it more comfortable to look at,

    How is this relevant to you? some external cards have a much broader range of temporal dithering frequencies which I think will help you. I reckon a modern AMD card will be most comfortable for you as they have the best temporal dithering algorithm of the cards I've analysed.

    Edit: you could also install ditherig from here and turn on temporal dithering for Intel and see how that feels.

      jrhack This is really interesting, thanks for sharing!

      I'll admit, I have no experience with this kind of stuff (Pretty much just been a Mac user and never bothered to customize anything), would this setup work with the M1 Macs? If so, I'll be trying one of these on my M1 MBA to see if it helps.

          Seagull Very interesting theory. I know that I'm very susceptible to PWM/flickering/strobing and so assume that temporal dithering is bothersome to my eyes. But, I've not heard of LCD inversion before now (and another mention I think you made of it responding to another of my posts). I just did the inversion tests at ufo test and find the flickering from inversion to be exactly the "noise" I feel like I see in many modern display setups that I can't get away from! So, I'm definitely going to research and investigate this more. Other than temporal dithering, what other remedies or treatments have you found for LCD inversion?

              bkdo If you take a look at the Sonnet eGPU chassis that I'm using (linked to in my original post) you'll see that one of the things they boast is being the first of these to be recommended by Apple for use with Macs. So, as long as your M1 MBA has a Thunderbolt port, I think this chassis should work and allow you the use of external, desktop-grade, graphics cards.

                jrhack

                Other than temporal dithering, you can change the monitor. Laptops may be worse than normal monitors as their energy efficient screens tend to use a more visible style of inversion. Lowering the resolution might help as well, particularly if you are reading text at the native resolution. Dimming the screen and blue light filters might help as well if your sensitivity to flicker is neurological.

                I added an edit to my original post incase you missed it. You can use a piece of software called ditherig to turn on temporal dithering in intel. There are a few settings to play with, I can't say which is best though as I haven't done any real analysis on it. If you turn dithering off completely you should see the colour depth visibly drop - ie more banding on colour gradients.

                    Seagull Thanks. I do have Ditherig installed on my desktop machine and honestly have never been able to tell a difference whether it's running or not (when it's set to disable dithering). I think my Intel HD 630 IG must have dithering disabled by default. If I use Ditherig to force just temporal dithering, then there is significant and noticable flickering. Otherwise, all the other settings look identical, both Spatio-Temporals, just Spatial, or all disabled, I can't tell any difference. But, just temporal looks awful, at least on my current desktop setup.

                    It remains a consideration for my work laptop, but being a work machine, I have to go through all sorts of approvals and exceptions with my employer in order to install something like that, and that one's very iffy being built just by some guy on the internet and not a reputable software company, so corporate infosec may or may not allow me to have that one on my work machine. But it's enough of a hassle to even attempt it that I've been putting it off.

                        jrhack

                        Interesting that you can see it flickering. AFAIK the temporal settings are never used unless you turn them on, perhaps because they are shit! spatial only is the default.

                        When turning dithering off you'll only see the difference on a laptop screen. Desktop monitors do their own dithering in addition to any graphics card dithering. Laptop screens are dumb, and rely on the graphics card to dither for them.

                        You might not need to install it, I believe all ditherig.exe does is change a registry key. I think you could write your own .bat file to make those changes, and set it to run on start up. You'd still need admin, but you could atleast show your employer exactly what it does and why,

                        • JTL replied to this.

                            Seagull I believe all ditherig.exe does is change a registry key

                            Incorrect. I looked into it and it directly writes to GPU state registers.

                            jrhack corporate infosec may or may not allow me to have that one on my work machine

                            Direct register access could be misused to do nasty things. I think a better solution could be developed in the future.

                                10 months later

                                UPDATE:

                                After a full year of using this eGPU, I'm happy to report that it alone solved this issue with this new laptop. I am getting all the comfort and visual ease of an old Nvidia 600 Series card from a laptop. I never did revert my Windows or update the video drivers again as my eyes quickly went back to normal and it largely became a non-issue (at least with this particular device).

                                I believe after first setting this up, I was trying too hard to find visual issues. I do that when experimenting with these things. Once I worked on it for several days and started to forget that I was trying out a new visual setup, everything seemed to return to normal between my eyes and these monitors that I've used for years. And now they do feel like they always did.

                                Here is an update on the items was going to continue working on:

                                1. I feel very confident that I am completely bypassing the laptop machine's onboard graphics. As soon as I routed video through the eGPU, the colors were noticeably "flatter" and more comfortable on my eyes and my continued experience over the past year is a return to normal viewing. No more acute eye strain or migraines attibutable to this machine that I've worked on most days for the past year.
                                2. Never pursued because of how my comfort was restored by the eGPU.
                                3. Never pursued because of how my comfort was restored by the eGPU.
                                4. I did purchase some additional cards but never got around to trying them out. I still plan on doing this, but really don't know when I'll get to it. I very strongly expect, however, that any card you're comfortable with in a desktop will be similarly comfortable when used with a laptop+eGPU.
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