PWM Flickering Monitors List

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cerbul

Limp Gawd
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May 14, 2012
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Does anyone knows if there is a list for all monitors in the world, with details regarding PWM flickering?
I am in the need to buy a glossy or semi glossy 23-24 inch IPS monitor that doesn't use PWM flickering and can't seem to find one.

And please, for the love of god, old dell/hp like coating is the hardest coating around, and can't be named "semi glossy"..
 
No list that I know of, though TFTCentral and Prad.de have both been testing newer models for PWM. Part of the problem is that PWM properties can change with monitor revisions, meaning that several displays with the same model number may have very different flickering.
 
I realize some folks are actually adversely affected by noticing PWM in LED monitors that use it, but funny how we never heard the complaint when dimming in CCFL displays used the same technology. They do however state PWM is more easily seen in LED backlighting.

http://www.tftcentral.co.uk/articles/pulse_width_modulation.htm

LG uses PWM in both the new 27EA83-D & 27EA83R-D 2560 x 1440p monitors which have not resulted in any major consumer complaints. Pretty sure the Asus PB278Q also employs PWM. Dell & Viewsonic do not use it in the U2713HM & the VP2770 but i realize the OP is looking for a 23-24".



Regards, :)
 
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If you actually study it you would understand that the reason people complain is not that they actually "see it", but they actually feel affected by it: THEIR EYES CANNOT ADAPT TO THE AMOUNT OF LIGHT INCOMING FROM THE SCREEN, EVERYTHING APPEARING TOO BRIGHT EVEN IF IS BARELY VISIBLE DUE TO LOW BRIGHTNESS SETTING.

Maybe those people that are now complaining about PWM being used with LED, skipped over CCFL for the exact same reason, but now they got difficulties in getting a proper CRT. And yes, some people simply refuse to be others lab rats.

Now read that 3 times, and try to understand it. No offence, but I really believe that people have the right to know what is happening behind the scene, so they get educated against bad practices in marketing, which are based on misleading and cheating.

Dell USES PWM, I got the living proof at work on a S2340L monitor.
There are reviews that are FAIR and actually state that those screens really do have PWM. Unfortunately some reviewers had their choice to remove the PWM testing from their reviews. Now that tells us a lot about their practices.
Trying to view "have not resulted in any major consumer complaints" as being perfectly fine, is just making me wish you were one of those people having problems with PWM.
 
As has been noted, if a person is prone to being affected by PWM, it's more likely to occur with LED than CCFL. That could be one reason why in the past people never made a big deal of it. Another reason could simply be that some people were bothered, but simply put up with it -- they didn't realize that monitors could be less eye-straining. And even if a person isn't super bothered by PWM, it is certainly possible that it adds to eye fatigue when using a monitor for hours on end, regardless if you consider yourself PWM sensitive or not.

As for a complete list of PWM-free monitors, I am not aware of one. If you want PWM-free at 23"-24", light coating, the ones I am aware of are:

Eizo 2336 (advertised as such, so long as brightness is above 20%).
Samsung 24" PLS (bleed issues, and pretty sure it's PWM free, but double-check that if interested).
Dell 2413 (I think ... but wide gamut and expensive).
Also look at BenQ, as they are going completely PWM-free for all future models. They do have a newer 24" IPS in their lineup, but I don't know what coating it uses.

Besides Eizo and BenQ, nobody else really advertises the fact their monitors are PWM-free, so there is always the possibility other revisions may differ.
 
U2413
OJjwugV.png



BL2411PT = typical grainy matte.
http://youtu.be/cnUDi_FcvYY
 
Silverfox1 said:
I realize some folks are actually adversely affected by noticing PWM in LED monitors that use it, but funny how we never heard the complaint when dimming in CCFL displays used the same technology. They do however state PWM is more easily seen in LED backlighting.
Click to expand...
This answer for me:
cerbul said:
Maybe those people that are now complaining about PWM being used with LED, skipped over CCFL for the exact same reason, but now they got difficulties in getting a proper CRT.
Click to expand...
Although I dont mind being a bit of a lab-rat if its actually leading somewhere better. PWM is just stupid on all levels. Its just unnecessary. Its a techy trick that has no business being used in something that is as important as a display you're looking at for 8+ hours a day.

As for the list its a bit complicated. Let us know what type of monitor you're looking for and I can tell you which ones there are.
 
- 1920x1080
- IPS,
- non grainy coating (glossy,semi glossy, or matte that is not grainy).
- 23 or 24 inches.
- No PWM, the under 20% pwm solution is fine, I can perfectly live with it.

U2413 is just fine at 114 cd being 20%. This means I won't have problems with it, especially that I use it at work during day.
However, is the coating grainy?
 
From what I can tell you already know all there are:
Eizo EV2336W - PLS semi-glossy
Eizo EV2436W - IPS grainy
BenQ BL2411PT - IPS probably not grainy. From the title words of the Prad review "ohne IPS-Glitzern".
U2413 - IPS. Not sure about AG but both TFT central and Prad have a reviews up.

There is not exactly much to look forward to either. I thougth HP would have been able to produce an alternative by now but I havent seen it. NEC they're still stuck on PWM. Samsung have their 'semi-PWM-free' models that might work for you. The next tier like LG, Philips etc all use PWM except in their 1440p and 29" models.
 
cerbul said:
U2413 is just fine at 114 cd being 20%. This means I won't have problems with it, especially that I use it at work during day.
However, is the coating grainy?
Click to expand...

I believe it has a light coating. But it is wide gamut, and you will lose some contrast (and probably encounter some other oddities) by using s-rgb mode.

I'd suggest the Eizo 2336 instead, unless you really want 24" 16:10. And in that case, I probably would recommend trying to hunt down a bleed-free Samsung PLS or finding out what coating that the BenQ model uses. Or go big with 27", as there are several models that are both light coating + PWM free at that size.

And a shame that NEC seems to be sticking with PWM. I am hoping that perhaps on their Pro models they will be PWM-free and they simply aren't advertising the fact -- but that probably is wishful thinking.
 
Looks like a flicker-free display list just popped-up at TFTCentral here. Not many displays in it yet, but it's a start.
 
cerbul said:
THEIR EYES CANNOT ADAPT TO THE AMOUNT OF LIGHT INCOMING FROM THE SCREEN, EVERYTHING APPEARING TOO BRIGHT EVEN IF IS BARELY VISIBLE DUE TO LOW BRIGHTNESS SETTING.
Click to expand...

Oh my god! maybe THATS what I have....
 
DF-1 said:
Oh my god! maybe THATS what I have....
Click to expand...

Most are tempted to lower brightness to compensate. In the contrary, the higher the brightness the lower the amount of time the screen will display black, so the easier will be for the eyes to adjust to the amount of light is really incoming. Many screens are PWM flicker free at 100% brightness, so is smart to test a bit the monitor with 100% brightness from monitor, and open up as many lights as possible in the room, and lower the software brightness from driver. This is just for test, to see if does help a bit. Obviously, this is not a solution, is just a trade off between contrast/clarity to see it PWM is the problem or not.

Best bet though is to try a panel that is PWM flicker free to see the difference, as lowering brightness from driver will degrade pretty bad the image quality, and might not be good enough to give you a clear answer.
 
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According to prad.de, the new Asus PB248Q is flicker-free, thanks to its 9,400 Hz frequency. ;)
 
cryogenesis said:
According to prad.de, the new Asus PB248Q is flicker-free, thanks to its 9,400 Hz frequency. ;)
Click to expand...
Agree that we need really high frequencies. I still can see PWM artifacts even at 1 kilohertz.

(e.g. Just adjust your brightness to near 0% and then view a fast high-resolution framerate-locked motion such as www.testufo.com/photo#photo=toronto-map.png&pps=1440 .... You'll see different looking motion artifacting during Brightness=0%, 50% and 100% -- similar to PWM repeat-image artifact, also talked about at TFT Central.)
 
The big issue that I'm having with the XL2420T is that it's so bright (like most 3D monitors) that I have to have it at like 5-10 (of 100) brightness to get a good picture quality. Which in turn gives me what I assume is PWM-related headaches. As cerbul explained earlier, it still shines just as brightly, just not as consistant. I for one will make sure I buy a PWM-free monitor next time...
 
I just received an email from HP customer care stating that in their new Z-Series they are not using PWM for LED dimming. To be honest I am not completely sure if they got my question right but it seems that LEDs are not dimmed in a continuous manner but by PAM (Pulse Amplitude Modulation), another pulse-based signal modulation technique. Since linear regulation currently is not the best choice for LED dimming it seems plausible that companies like BenQ also use PAM in their "flicker free" advertised models.
 
BenQ are using Direct Current according to their marketing material and info on their website.
 
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