i'm attempting to see if it's actually possible to find a modern-ish laptop that is as comfortable to use as my ancient 2012 Lenovo Yoga 13 1st Gen (which has a LG 1600x900 6-bit IPS panel, for reference)
first laptop i'm trying is a Lenovo ThinkPad T480. found it used in near-mint condition for $250ish
not sure if i'm keeping this specific one but the most important thing i've learned is downgrading to Windows 10 1809 actually matters!!
i5 8th gen, 32GB RAM, UHD 620, 1080p non-touch
panel Innolux N140HCA-EAB 6bit. has obivious medium flicker depth PWM on grays when filming at 240hz at all brightness levels, even in BIOS.
once again the NotebookCheck pwm """free""" rating is NOT accurate!!
in addition to this T480, i will also be testing out a T480S soon. it hasn't delivered yet so i don't know which 1080p panel that one will have
trying to run it on Win11 23H2: failed
mine shipped with Win11 23H2, 2023 BIOS version, 2021 intel drivers
after setting it up, it was of course still easier to look at than most MacBooks -- especially because of matte, however, despite that, something was definitely very off about it
ok, first attempt… the usual stuff, disable DPST with dpst-control, disable adaptive refresh and lock 60hz in intel graphics settings, disable dithering with ditherig.exe (successfully got banding), and disable WindowsColorSystem Calibration Loader in Task Scheduler. i also tried to disable ACM but the option wasn't there at all
immediately ran into a problem: the modern command center has "brightness/contrast enhancement" sliders which don't actually have any "off" value. they start at irregular numbers and trying to set them to 0, 50, or 100 gives a totally inaccurate result. i knew that i at least needed to downgrade to old drivers
trying old drivers on Win11: still failed
uninstalled 2021 drivers and installed June 2017 Intel drivers. downgrading the drivers also downgrades Command Center to UHD Control Panel instead. noticeable improvement, and could finally disable contrast enhancement, so for a little while i thought i "fixed it"
unfortunately, one of the biggest issues (that i typically associate with Apple devices) is here: the "false 3D depth" effect. even with the older drivers this is extremely noticeable in Win11
looking at any "large zoomed-in object" on the screen in Win11 23H2 makes my eyes feel like they need to "look closer" to see it, there is unnatural depth on what should physically be a flat surface. and in general the screen feels too close to you no matter how far you put it out on the desk
the strain caused by this kind of effect is one of the worst (it's the biggest reason almost all MacBooks are unusable for me)
tried to use the laptop for a few hours with this Win11 config and even though it wasn't "as" bad as the even worse 2021 drivers, i still got super strained, i felt so tired… the screen looked very blurry for me at normal distance and "made me think i want glasses" even though "good" screens look perfectly crisp at the same distance
i noticed when looking closely at black pixelated unsmoothed text on white BG, or even the pixelated Win95 mouse cursor theme, i could notice blue and red aliasing on the edges of the black pixels, almost like subpixel rendering (even though ClearType was off). maybe this is part of what's behind the "false 3D" effect
the worst part is that on Win11, even disabling Intel graphics and using MS Basic Display Adapter did not fix it!!
however…
but Win10 1809 downgrade IMPROVED IT!
even with all that, turns out it was still NOT the LCD panel's fault!
wiped Win11 entirely, installed Win10 1809 17763.107
even the installer already looked better than anything in Win11 lol
installed Windows without WiFi so i was then able to install Winaero Tweaker over a USB to disable windows updates, maintenance tasks, auto-installed apps, store update, driver updates, etc. before enabling WiFi again
installed the same June 2017 Intel graphics drivers again and reapplied all of the same previous steps with disabling DPST, adaptive refresh, etc…
FINALLY the "false sense of 3D depth effect" is significantly minimized, it's possibly gone (but don't take my word for that though lol) - at least, it's minuscule enough that it's a totally different feeling compared to 11 and wayyyyy less strain
looking at some of the same screenshots i took on Win11 whenever i experienced this effect…
on Win10 1809, the effect doesn't happen on them -- i finally "don't feel like i constantly need to focus my eyes closer"!! the screen is obviously flatter
in addition, i noticed that on 1809 i cannot see that "red subpixel weirdness" around black pixels on a white background anymore!
(for example, the Win95 cursor theme is now just black & white to my eyes and no longer has any noticeable "red edges" to it anymore)
also, weirdly, taking close up pictures of the screen became easier. before, taking a camera picture of a white background on Win11, i would only get a grainy look to the subpixels on my camera, i just thought that was a side effect of the matte coating at first. but on Win10 1809 -- i can finally take a close up picture of the screen and actually see the individual RGB subpixels
my guess is that on Win11 the white pixels were flickering intensely enough that my camera couldn't catch up which is what was making it look grainier to the camera……
i'm now using the laptop in the same exact spot i was using it earlier today with Win11 -- and now, with Win10 1809, it does not look blurry anymore, and while writing this i'm not feeling tired like i did before!!
downgrading Win10 1809 finally made this screen "actually resemble something normal" to me
the takeaway
2023 BIOS version on a laptop probably doesn't matter in this case
Intel driver version matters a pretty good amount
Windows version VERY MUCH matters, Win11 23H2 is not usable even with basic display adapter!
Windows 10 1809 has already fixed so many of the issues I had with 23H2 -- and in a very noticeable and even detectable way (i see way less "subpixel fringing" around all pure black and other high-contrast pixels that of course shouldn't have any. screen no longer feels blurry to me)
however, PWM inherent to the display panel itself is still an issue
still unsure about this T480 though
even though my ancient 2012 Lenovo Yoga 13 also has "PWM at all brightness levels" and that one remains perfectly usable for me -- in comparison, the flicker depth on this T480 appears more intense on camera than the Yoga…
even before i actually tested for PWM, i was feeling like i could notice the PWM myself especially on dark mode apps, even on Win10 (it is generally easy for me to tell apart hardware backlight PWM symptoms from dithering/color symptoms -- because color symptoms are much worse for me)
PWM on this T480 is definitely more of an issue than the PWM on my 2012 Yoga. it's a letdown since i chose this laptop as most said it was """""""pwm-free"""""""
also, the screen is very dim, which is not necessarily a bad thing, but i realized that it's more dim than even my 2012 Yoga which is already very dim, so that definitely annoys me
but on the other, very positive side, downgrading to 1809 finally seems to fix the temporal dithering and other "not exactly dithering but possibly even worse color techniques" that were sooooo bad on Win11
this post pretty much remained clear on Win10 1809 for the whole time i've been writing it, compared to Win11 23H2 where it would start going blurry for me in like 5 seconds
however, especially because of the PWM disappointment, at this point i cannot yet decide whether i like this T480 or not. will need to use Win10 for longer and also waiting to compare it to the T480S i receive -- i'll keep y'all posted here
TLDR
AVOID modern Windows 11 versions on integrated graphics. Unusable regardless of drivers.
Windows 10 1809 actually DOES improve things, noticeably, and is not placebo. Ensure you also downgrade graphics drivers to the oldest possible version.
Finally, be wary of PWM on Innolux panels in ThinkPads