Has anyone had any success with g-sync or freesync laptops?
Laptop for those with PWM and flickering sensitivity
Disagree totally. Like I wrote, I've had this for more than 25 years and particulary some 15 years ago, when I had no idea what was causing it, except for that the cause is a computer monitor, I was using PWM monitors constantly and my eyes were constantly bloodshot and very irritated, but once I learned about PWM and was able to get a PWM free monitor, the problem disappeared completely.
It is just in recent years that manufactureres have started to utilize the FRC/Temporal dithering with many screens that also cause flicker, this problem has come back. But always when I find a device without Temporal Dithering and use it with brightness levels where there is no PWM, the problem disappears.
The thing is that it does not seem to be possible to eliminate the flicker anymore with most devices. Even if there is no PWM, there is Temporal dithering and there is no way to remove that. Programs like Ditherig or Iris do not help at all.
There is nothing mystical abou this problem. It is very much like excercising muscles. If you excercise too much, your muscles will get sore, but when you stop it, they will heal. Similarly, as the optic nerve senses the flicker it will get strained and strain the muscles in the eye, which cause the bloodshot eyes, but when you stop doing what causes it, then the muscles / nerves heal.
I think the issue is that not everyone is affected by PWM, Muscle strain wouldnt be immediate, a 'bad' screen device will affect me almost immediately
I have a CCFL monitor that has PWM and I used it for 11ish years with no problems, I didnt know what PWM was!
I had an OLED samsung S6 phone, had PWM was fine untill I dropped it
Then I got other devices with PWM and they were not fine, then I got other devices that dont have PWM and they were not fine, I've returned motorola phones with and without pwm and laptops without PWM but they still caused problems
The only consistent thing for me is that devices that are using technology up to around -2018 are OK, newer items are NOT ok for me. - my newest OK device is an Ipad from 2018 but I have to use reduce white point. There are some exceptions though but I think this is firmware related OR I have irreversably damaged myself
Anyway - how can we tell if we have a 10 bit screen? I would also like to hoard old lenvo machines as I've had success with them although one died on me recently.
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I have now tested 5 laptops in a few weeks:
Matebook X Pro 2020 - LCD pwm at 60%, used at higher brightness but still caused some eye strain after several hours of use, not usable for work purposes as it would require daily 10 h usage.
Asus Zenbook UX393 - LCD without PWM, but causing much more eye strain than Matebook, probably Temporal dithering?
Dell XPS 9300 - LCD with PWM at 25%, but used at higher brightness, similar to one above, might be a bit less eye strain, but still difficult for work usage
Lenovo Legion 5 Pro - LCD witout PWM, Nvidia 3060 discrete, 165Hz refresh rate. Seems to not cause eye strain, at least not that bad. I have to try it a couple of more days at work. Suspected cause of not causing eye strain is Nvidia discrete graphics and 165 Hz refresh rate.
Asus Zenbook Flip U371 - OLED with PWM below 52 %, 60 Hz slight lowring of brightness above 52%, similar to PWM, but does not seem to cause major eye strain. I will still keep testing.. Suspected reason of not causing eye strain: 10bit OLED without FRC / Temporal dithering and lack of actual PWM above 52%. The slight eye strain that seem to feel might be due to the 60Hz slight banding above 52%, but will it be a problem after using 10h on consecutive days, remains to be seen.
@HAL9000 there are very few actual 10bit screens in the market, none for laptops that I know of. Mostly high end photo editing screens.
I was also able to use CCFL screens with PWM (at least some of those) with minor eye strain. That is because CCFL dims and lights up slowly, so the flicker is not as abrubpt as with LED and OLED.
I personally think that the newer devices are problematic as manufacturers are squeezing more colors out of lower quality panels with Temporal dithring / FRC.
Now why this does not seem to be the case with the Lenovo Nvidia combo is that I disabled the integrated GPU from the bios and use only Nvidia GPU, which might have different type of dithering or no dithering at all. But who knows.
The problem with the non PWM screens causing eye strain is that the eye strain is not immediat like with PWM. it requires several hours of usage. So often times I might think that the screen is OK, but after the second workday where I've used the screen for 8 h or so, I see my eyes being bloodshot. This is similar to CCFL PWM. if ai was gaming every night for several hours, my eyes started to get strained and bloodshot in a couple of days.
This does not happen with my HP ZR40w27 display that does not have PWM. (some 8 years old) or e.g. with Surface Pro 2 at full brighness. Or with Sony televisions without PWM. Even if I would have strained eyes from PWM, I can rest my eyes using the HP display or a sony TV.
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@HAL9000 if I may ask what kind of problem do you get with some screens? Do you also get red eyes?
The bloodshot eyes with PWM seem to be very common and has also been confirmed in some studies.
Some get migraines - I do have a migraine once in a year or two, but it is not related to using screen at all. I can get it in the middle of the night, morning when I wake up or at the golf course. It is a classic migraine with sawtooth vision and cognition problems, lasts for an hour or so with lingering minor headache that can last a couple of hours and have some residue a few days after. Not a bad migraine at all. In fact, I
ve never gotten a migraine while using a screen or shortly after.
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Migraines. My doctor tells me they are migraines, but I previously got migraines and these feel slightly different to the ones that 'bad' devices (screens) give me.
PWM will make my eyes feel bad though, strained and yes sometimes they go red and itchy and I can feel the muscles all round the eye and it gets quite bad, however then the headache will start and takeover and get worse and worse (I massively limit my time on PWM oled phones I have to use for work) As flicker is one of my triggers for my 'normal' migraines
A 'bad' device will begin to affect me within seconds, I can feel it in my head a burning pressure that gets worse and worse and then the pain starts, sometimes just at the top of my head but it feels deep inside like a pressure, the pain is very significant and it is difficult to concentrate and I sometimes feel dizzy as well, this will last for 1-3 days before it goes away - during this time I have to avoid the 'bad' device otherwise the symptoms do not get better. I can and do use my 'good' devices while I have the pain (I have had to learn to function whilst having migraines even before this) Everything I buy is PWM free apart from my very old CCFL screens and potentially television.
(I have tried diet changes / suppliments, eye tests / glasses, exercise helps a bit to dull the pain sometimes but nothing I do will fix the issue or act as a preventative it seems)
Simply using an external screen doesnt help, Ive also had little help from disabling drivers changing settings disabling dithering (or trying to) etc, if a device is bad its bad and so far I havent found a 100% way to fix it. Recently as well I've expereinced software (games) that were preiously fine on my 'good' hardware, but after the game is updated it triggers the same symptoms.
My Nvidia 1060 laptop is fine for me to use, I have had another Nvida laptop that was ok but it failed, recently I returned a HP Nvidia laptop as it was not ok for me to use
You have an interesting situation with the problems starting on previously found OK devices.
I have not experienced anything like that during the 25 years I've had this.
I also have had no success in getting a device to be OK by disabling dithering with ditherig.exe or anything else. No matter if I use polarized sunglasses, blue blocking glasses or computer glasses or no glasses or a glass of milk.
If there is PWM it is always bad, less bad with CCFL.
As for the temporal dithering or FRC, I've not yet been able to fully confirm. On a previous job I used a HP laptop that did not have PWM, but had the temporal dithering type of eye strain and when I connected that laptop to an external display, I was fine.
So for me it is kinda straight forward. Most new devices with great screens, even without PMW will cause bloodshot eyes. In that sense it is even more straight forward (or should be e.g. for doctors) as they can actually verify my bloodshot eyes. For persons with migraines it can be more difficult ans migraine is difficult to verify and is oftentimes thought to be associated with stress. This must make it more frustrating, as e.g. for me, migraine is not associated with stess, but a couple of times people have inferred that is is related to stress, though it is completely and absolutely random. I can get it on a long holiday while relaxing by the lake, or sitting in an aeroplane or sleeping.
But the red eyes are quite a physically verifyable symptom, but still all doctors try to infer that it is something psychological, while clearly it is not. Or then I have some phychological super powers as my eyes will turn red in 30 min with a display that has PWM at 99% but not 100%. My magic psychological powers are able to sense the 1% difference in brighness and absolutely without fail turn my eyes bloodshot in 30 min
@Maxx I've always had Lenovo laptops and I love them overall.
But since eye-fatique is getting worse i'm more dedicated to find a solution.
The feedback you give on Lenovo Legion 5 Pro does give me a spark of hope, since I'm really interested in this laptop.
And i'm glad you can disable igpu in the bios, I didn't think this was possible.
Do you have any instructions?
weasley I'm still testing the lenovo today and tomorrow before I decide if it is OK Or not. Yesterday I concluded that the Asus with the OLED would be ok to use a few hours a day, but now waking up I do have a bit irritated eyes from using it yesterday some 8h.
I still have to test the Lenovo similarly today to be sure is it better or not
The igpu disabling does not require any instructions. Just hit f2 to enter bios and select from a dropdown. Actually, I think it was disabled by default.
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I think the issue I have with some software, such as games is if they update the game engine or whatever or change the way colors are presented / flicker etc is what gets me. I want to be able to try things with a 144hz screen but at 75hz still an issue. There are some games that I've played and refunded that trigger my symptoms immediately so I believe its also related to game engines etc again.
I get what you mean though, it can be very stressful to be told you're stressed when you're not!
The PWM / eye bloodshot is easy to proove as you say. Think of a strobe light when describing it, think what your iris is doing, opening and closing rapidly as the light flickers and this with slight eye movment causes the muscle pain around the eyes.
Maybe with flicker at 1000+hz some people have eyes that still react in such a way thus making the eyes tired and red, then people like me also get migraines from it - but again I still dont think these are migraines / they are a different sort of migraine.
I'm 3 or 4 days into one now, its levelling off. I have a Lenovo t440 on the way that should have a TN screen so I have some hope that my migraine is totally gone soon and this new old laptop will be ok
I have clear evidence that my eyes get red with PWM of 2400Hz. I had Sony Xperia phone that had 2400 Hz PWM at 33 brightness. When ever I let auto brightness lower it or manually lowered it, my eyes got red. Finally I just kept it manually over 33 and I had zero problems with it for the 2,5 years that I had it.
I know it sounds unbelievable and sites like notebookcheck also kinda claim that it is not possible to sense such high frequencies, but my eyes do without a doubt. Anyone could verify this by seeing my red eyes.
If the ears sense 20Khz why would the optic nerve be able to sense 2,5Khz? I dont claim that I see the flicker, the flicker just makes my eyes bloodshot.
I dont mean to hijack this thred but I've recieved my Lenovo T440, intel 4300u HD4600 - although even after updating the drivers its reported as 'intel HD graphics family' - I know its not a new machine and used is hit and miss.
Either way as I suspected / hoped this machine is totally fine for me to use - it doesnt appear to have PWM but as it was used it is not in amazing condition but refurbished to a high standard and around 1/3 the price of the HP envy that I returned recently.
Its got a HD TN screen that is very poor even for a TN and very dim - but this is good for me. I actually have 2 other IPS screens that should fit so I can experiment with that.
Hoarding old Lenovos appears to be the way forward at least for me. Annoyingly I can buy the same machine again for cheaper now but I'll hold off I think.
I do agree with the comments on Notebookcheck, sometimes they're wrong as well and devices they test have PWM - but this may be regional / panel differences, but yes I do believe some people, myself included can detect and be affected by very high frequency flicker / PWM.
just a status update. I had to return the Lenovo Legion 5 Pro. I was able to used it a full workday, but in the afternoon my eyes started to feel strained and then the whole evening my eyes were irritated and dry. Not that badly bloodshot as with a PWM screen, but clearly there is some flicker in that screen, maybe from temporal dithering.
Again, I could rest my eyes with the HP desktop monitor or a Sony TV after using the laptop for a day. So it is not my eyes per se, it is the bad display.
I'm still testing the Asus Oled. Not sure yet, as I've not had a chance to used it like I would on a typical workday. But I'm pretty sure it is better than the LCD screens. I use it over 52 brightness where there is only a minor dip in the brightness at 60Hz.
I was able to use Galaxy S2 6 years ago without problems, it was and has been practically the Only Oled phone without PWM.
Maxx I have clear evidence that my eyes get red with PWM of 2400Hz. I had Sony Xperia phone that had 2400 Hz PWM at 33 brightness. When ever I let auto brightness lower it or manually lowered it, my eyes got red. Finally I just kept it manually over 33 and I had zero problems with it for the 2,5 years that I had it.
I once read a paper from the "lighting industry" that claim that some of the effects of PWM persist up to around 10KHz, but I'm not entirely sure of the methodology involved.