This thread deals specifically with the 'Auto brightness backlight flicker'. Which only occurs when the phone is set to 'Auto brightness'.
This does not deal with the various other screen glitches, or the constant flicker at various brightness levels when looking at grey screens.
Please do not get the two issues confused.
_____________________________________________________________________________________________
I have observed a few patterns, on two seperate handsets with the same symptoms....
*Firstly, the flicker occurs while the CPU is under load, and particularly at lower battery levels.
*Secondly, The flicker occurs momentarily when you plug in a charger.
*Thirdly, The flicker doesn't occur while the device is charging.
*Fourthly (is that even a word), The flicker is often seen immediately after a screen settles, such as when the screen stops moving after scrolling.
All of these things are evidence of a power management issue. As if the backlight voltage is not being regulated correctly.
I did some more testing over the last few hours and have found something interesting. If you go to 'Settings' - 'Developer Options' - and enable 'Show Screen Updates', your phone will blink the screen different colours whenever the screen is updated. I found that when the screen settles, the screen is updated one final time, just a moment after it has settled. This is exactly when the flicker occurs. As i see it, this is further evidence that the flicker is power management related.
It seems to me that when the CPU goes from load to idle and changes its power draw, the backlight voltage regulation does not filter these fluctuations and the backlight flickers.
The question is, can this be altered either by the power management built in to the kernel, or by other power management software? Or is it a physical design flaw in the power regulation circuit?
The fact that the fluctuation only seems to occur when the brightness is set to auto leads me to believe that it indeed can be fixed with software.
If it was a physical supply voltage fluctuation when the CPU goes from load to idle, it would surely flicker all the time, not only on Auto Brightness.
I assume that the CPU voltage is altered by the kernel as the load level changes.
My question is, if the governor is changed to one which doesn't allow the CPU to scale or voltage step, does the issue go away?
Is there anyone out there who has rooted their device and can test my theory? I don't want to root my device as I may need to send it back DOA (it's only a day old).
If you can change the governor to a profile which doesn't allow stepping or voltage adjustment (100% Voltage and Frequency all the time), and the problem goes away, we have an answer and HTC can work on developing a new Kernel to fix the issue.
Thanks!!
Sentinel196 said:
Please do not get the two issues confused.
Click to expand...
Click to collapse
It is highly likely that all the graphics issues are related. This includes various types of flickering, notification bar corruption, and strange bands in the camera app. Similar issues occurred with the Teg3 Asus Prime when it launched and all were corrected with updates. There are also some performance variations that can be seen in benchmarks when the issues are at their peak that go away when the phone's rebooted.
Nvidia, not HTC (or the devs) controls the Teg3 low-level code, drivers, and kernel. All this has been discussed in the other two threads. As has a communication from HTC UK received yesterday that they've identified the issue and will be issuing an update (not 1.29) to address it.
64 pages of flickering and graphics issues discussion here:
http://forum.xda-developers.com/showthread.php?t=1617009
Thanks for the info. I'm well aware of the other thread and have been following it closely.
Not looking to start a debate about the cause and if the problems are related. Just looking for someone to help me test my theory.
Sentinel196 said:
This thread deals specifically with the 'Auto brightness backlight flicker'. Which only occurs when the phone is set to 'Auto brightness'.
This does not deal with the various other screen glitches, or the constant flicker at various brightness levels when looking at grey screens.
Please do not get the two issues confused.
_____________________________________________________________________________________________
I have observed a few patterns, on two seperate handsets with the same symptoms....
*Firstly, the flicker occurs while the CPU is under load, and particularly at lower battery levels.
*Secondly, The flicker occurs momentarily when you plug in a charger.
*Thirdly, The flicker doesn't occur while the device is charging.
*Fourthly (is that even a word), The flicker is often seen immediately after a screen settles, such as when the screen stops moving after scrolling.
All of these things are evidence of a power management issue. As if the backlight voltage is not being regulated correctly.
I did some more testing over the last few hours and have found something interesting. If you go to 'Settings' - 'Developer Options' - and enable 'Show Screen Updates', your phone will blink the screen different colours whenever the screen is updated. I found that when the screen settles, the screen is updated one final time, just a moment after it has settled. This is exactly when the flicker occurs. As i see it, this is further evidence that the flicker is power management related.
It seems to me that when the CPU goes from load to idle and changes its power draw, the backlight voltage regulation does not filter these fluctuations and the backlight flickers.
The question is, can this be altered either by the power management built in to the kernel, or by other power management software? Or is it a physical design flaw in the power regulation circuit?
The fact that the fluctuation only seems to occur when the brightness is set to auto leads me to believe that it indeed can be fixed with software.
If it was a physical supply voltage fluctuation when the CPU goes from load to idle, it would surely flicker all the time, not only on Auto Brightness.
I assume that the CPU voltage is altered by the kernel as the load level changes.
My question is, if the governor is changed to one which doesn't allow the CPU to scale or voltage step, does the issue go away?
Is there anyone out there who has rooted their device and can test my theory? I don't want to root my device as I may need to send it back DOA (it's only a day old).
If you can change the governor to a profile which doesn't allow stepping or voltage adjustment (100% Voltage and Frequency all the time), and the problem goes away, we have an answer and HTC can work on developing a new Kernel to fix the issue.
Thanks!!
Click to expand...
Click to collapse
i like the theory, but on the 4 out of 6 handsets i've had, the flicker started off only on auto brightness, then got worse over a day or two, and then would develop into a constant flicker, regardless of backlight settings.
Well i really hope thats not the case here as I only have 10 hours left of DOA return window. :S
Sentinel196 said:
This thread deals specifically with the 'Auto brightness backlight flicker'. Which only occurs when the phone is set to 'Auto brightness'.
This does not deal with the various other screen glitches, or the constant flicker at various brightness levels when looking at grey screens.
Please do not get the two issues confused.
_____________________________________________________________________________________________
I have observed a few patterns, on two seperate handsets with the same symptoms....
*Firstly, the flicker occurs while the CPU is under load, and particularly at lower battery levels.
*Secondly, The flicker occurs momentarily when you plug in a charger.
*Thirdly, The flicker doesn't occur while the device is charging.
*Fourthly (is that even a word), The flicker is often seen immediately after a screen settles, such as when the screen stops moving after scrolling.
All of these things are evidence of a power management issue. As if the backlight voltage is not being regulated correctly.
I did some more testing over the last few hours and have found something interesting. If you go to 'Settings' - 'Developer Options' - and enable 'Show Screen Updates', your phone will blink the screen different colours whenever the screen is updated. I found that when the screen settles, the screen is updated one final time, just a moment after it has settled. This is exactly when the flicker occurs. As i see it, this is further evidence that the flicker is power management related.
It seems to me that when the CPU goes from load to idle and changes its power draw, the backlight voltage regulation does not filter these fluctuations and the backlight flickers.
The question is, can this be altered either by the power management built in to the kernel, or by other power management software? Or is it a physical design flaw in the power regulation circuit?
The fact that the fluctuation only seems to occur when the brightness is set to auto leads me to believe that it indeed can be fixed with software.
If it was a physical supply voltage fluctuation when the CPU goes from load to idle, it would surely flicker all the time, not only on Auto Brightness.
I assume that the CPU voltage is altered by the kernel as the load level changes.
My question is, if the governor is changed to one which doesn't allow the CPU to scale or voltage step, does the issue go away?
Is there anyone out there who has rooted their device and can test my theory? I don't want to root my device as I may need to send it back DOA (it's only a day old).
If you can change the governor to a profile which doesn't allow stepping or voltage adjustment (100% Voltage and Frequency all the time), and the problem goes away, we have an answer and HTC can work on developing a new Kernel to fix the issue.
Thanks!!
Click to expand...
Click to collapse
As for your first issue regarding flickering at lower power levels, have you tried accessing the power-saving settings and turning off the setting which changes brightness at lower battery levels? The method of accessing power-saving settings is outlined here: http://forum.xda-developers.com/showthread.php?t=1627517
oh well again i guess
NVIDIA PRISM Display Technology - PRISM (or Pixel Rendering Intensity and Saturation Management) reduces a mobile device’s backlight power while simultaneously enhancing the pixel color to deliver the same visual quality with substantially extended battery life.
Click to expand...
Click to collapse
http://www.nvidia.com/object/tegra-3-processor.html
Thanks. I'll test that out to see if it makes a difference too.
Still hopeful someone with root can test changing the scaling setting for the CPU.
hamdir said:
oh well again i guess
Click to expand...
Click to collapse
It's a great guess. The sensitivity of this being wonky was one of the things causing problems on the Prime. It also affected individual devices differently, was worse in certain apps, and was most prominent when the display was showing a predominantly dark background.
So how did they fix it?
Sentinel196 said:
So how did they fix it?
Click to expand...
Click to collapse
Drivers and low-level code. And it took four updates to get everything stabilized (battery usage, CPU performance/stepping, graphics). This has little to do with HTC (the XL having no similar issues) and everything to do with Nvidia.
designgears said:
Pretty sure this has to do with the crappy gfx drivers. The same thing that cause the camera to have issues and the notification bar. While I had the international one x, the phone benched really well while those problems weren't happening, but as soon as I was able to reproduce them and ran the tests again, score was reduced by a lot.
I could reboot the phone and the problems would go away, only to come back after some use.
Click to expand...
Click to collapse
http://forum.xda-developers.com/showthread.php?t=1619432
OK. So it looks like I'm on the right track and it's hopeful that this can be fixed in future updates
Thanks for the info.
Sentinel196 said:
OK. So it looks like I'm on the right track and it's hopeful that this can be fixed in future updates
Thanks for the info.
Click to expand...
Click to collapse
There were a bunch of really smart people and quite a few established devs on the Prime forum when it launched. When these problems started to occur, everyone was equally flummoxed. The one question that never was answered is why devices with identical h/w and s/w would perform differently and react to updates differently. Clearly they shouldn't. No one believed the issues could be corrected with s/w alone. Somehow they were. Neither Asus nor Nvidia ever answered the question as to the differences in individual device behavior. I don't blame anyone here for being skeptical. Something really funky is going on with Teg3 that no one will probably every truly understand. Truthfully, if the HSPA version of the One X was S4 too I’d have preferred it.
I guess it just comes down to variation in the tolerances of components.
I used to work in mil-spec electronics design and manufacturing and even with the tightest possible manufacturing tolerances, there was always variation.
BarryH_GEG said:
There were a bunch of really smart people and quite a few established devs on the Prime forum when it launched. When these problems started to occur, everyone was equally flummoxed. The one question that never was answered is why devices with identical h/w and s/w would perform differently and react to updates differently. Clearly they shouldn't. No one believed the issues could be corrected with s/w alone. Somehow they were. Neither Asus nor Nvidia ever answered the question as to the differences in individual device behavior. I don't blame anyone here for being skeptical. Something really funky is going on with Teg3 that no one will probably every truly understand. Truthfully, if the HSPA version of the One X was S4 too I’d have preferred it.
Click to expand...
Click to collapse
there is a lot to love about the Tegra mate, h264 video playback is amazing on it, also android is on steroids thanks to T3
but yes im with you on the issues, semi accurate reported crazy silicon issues, i don't find it hard to image that the Prism feature is just a cover up too
it was added later on the nvidia specs page
So, to sum this up guys - are you closer to say that flickering problem is actually only a matter of s/w?
I'm wondering how long it'll take HTC to admit that there are real issues and then how long we'll have to wait for the possible solution - replace, repair or just update the firmware :O
Anyways, this made me a bit more optimistic, since with unlocked bootloader it'd be hard to fight for the replacement
Sentinel196 said:
I guess it just comes down to variation in the tolerances of components.
I used to work in mil-spec electronics design and manufacturing and even with the tightest possible manufacturing tolerances, there was always variation.
Click to expand...
Click to collapse
Here's my theory. Nvidia's having yield issues with Teg3 and what's shippable is functional but varies in spec to a degree. The s/w is anticipating a range of responses from the h/w and what it's receiving is outside that range causing it to bork. Nvidia's "fix" is a combination of taming the h/w via low-level code and expanding what the s/w and drivers are capable of interpreting. And because of variations between chips, it's hard to test in a lab which is why it took four updates to resolve the Prime's issues. Again, just my theory.
I also believe both Asus and HTC were victims. There's no way both companies could be so ****ty at testing to have not caught this pre-production. My second theory is that Nvidia provided hand-picked chips early on that were right on spec and consistent so all the internal testing passed and units sent to professional reviewers all behaved optimally. It wasn't until production that inconsistencies between chips started to rear their ugly heads. Add to this that Nvidia's code, their drivers, and the kernel (still GB vs. ICS on the XL) are proprietary so both Asus and HTC are 100% dependent on them to resolve these issues.
Pretty ugly if I'm right.
BarryH_GEG said:
Here's my theory. Nvidia's having yield issues with Teg3 and what's shippable is functional but varies in spec to a degree. The s/w is anticipating a range of responses from the h/w and what it's receiving is outside that range causing it to bork. Nvidia's "fix" is a combination of taming the h/w via low-level code and expanding what the s/w and drivers are capable of interpreting. And because of variations between chips, it's hard to test in a lab which is why it took four updates to resolve the Prime's issues. Again, just my theory.
I also believe both Asus and HTC were victims. There's no way both companies could be so ****ty at testing to have not caught this pre-production. My second theory is that Nvidia provided hand-picked chips early on that were right on spec and consistent so all the internal testing passed and units sent to professional reviewers all behaved optimally. It wasn't until production that inconsistencies between chips started to rear their ugly heads. Add to this that Nvidia's code, their drivers, and the kernel (still GB vs. ICS on the XL) are proprietary so both Asus and HTC are 100% dependent on them to resolve these issues.
Pretty ugly if I'm right.
Click to expand...
Click to collapse
not hard to believe
one of the advertised features of Gerfoce 6 series was the pure video decoder, the entire 1st gen batch did not even work, it was broken in the silicon and Nvidia did not admit it until much later when the series was obsolete
hamdir said:
not hard to believe
one of the advertised features of Gerfoce 6 series was the pure video decoder, the entire 1st gen batch did not even work, it was broken in the silicon and Nvidia did not admit it until much later when the series was obsolete
Click to expand...
Click to collapse
Then you'll find this fascinating. Nvidia's PR exceeds their product’s capabilities by about 2:1.
http://semiaccurate.com/2012/05/01/why-cant-nvidia-supply-keplergk104gtx680/
BarryH_GEG said:
Then you'll find this fascinating. Nvidia's PR exceeds their product’s capabilities by about 2:1.
http://semiaccurate.com/2012/05/01/why-cant-nvidia-supply-keplergk104gtx680/
Click to expand...
Click to collapse
still you cant live without them bro, in our CG industry they are pioneers now thanks to their cuda cores and language
im sure they let marketing tint their transparency but semi accurate goes too far
Related
I have noticed that my screen is flickering ever so slightly in all applications. it is bearable but slightly annoying. Could this be hardware related and will I have grounds for a warrenty replacement? should I wait and see if any OTAs resolve it?
Everything is stock. Brightness is set to auto.
I have problems with shadowgun crashing when there is an explosion etc. possibly related?
Sent from my HTC One X using XDA
Yeah, i noticed this too on my One X I've mostly seen it while my mobile data connection was on, and it seems to decrease a lot but not completely disappear when it's off. I also got a weird message yesterday while charging, saying something along the lines of "your phone is using too much current, -" (the message was in dutch, not sure what the exact message is in english) my phone turned off before I could completely read it. I wonder if those issues are somehow related. Maybe the screens backlight isn't getting enough power when the radio is on. Anyways, I'm not an expert, so don't quote me on that.
I also heard the tegra 3 drivers are buggy, so shadowgun crashing and performance drops etc. will hopefully be resolved in future updates.
I've got it as well I think it's a driver issue the last thing I want to do is go for a replacement and that to have more dud stuff as this is the only dud thing on mine. Everything else is fine apart from flickers now and then.
Sent from my HTC One X using Tapatalk 2
See developer option
JimmyEatFood said:
I have noticed that my screen is flickering ever so slightly in all applications. it is bearable but slightly annoying. Could this be hardware related and will I have grounds for a warrenty replacement? should I wait and see if any OTAs resolve it?
Everything is stock. Brightness is set to auto.
I have problems with shadowgun crashing when there is an explosion etc. possibly related?
Sent from my HTC One X using XDA
Click to expand...
Click to collapse
hey jimmy go to Menu->settings-> Developer options and untick all the option restart your phone and magic..... screen flickering will disappear
---------- Post added at 11:46 PM ---------- Previous post was at 11:34 PM ----------
backstabz0r said:
Yeah, i noticed this too on my One X I've mostly seen it while my mobile data connection was on, and it seems to decrease a lot but not completely disappear when it's off. I also got a weird message yesterday while charging, saying something along the lines of "your phone is using too much current, -" (the message was in dutch, not sure what the exact message is in english) my phone turned off before I could completely read it. I wonder if those issues are somehow related. Maybe the screens backlight isn't getting enough power when the radio is on. Anyways, I'm not an expert, so don't quote me on that.
I also heard the tegra 3 drivers are buggy, so shadowgun crashing and performance drops etc. will hopefully be resolved in future updates.
Click to expand...
Click to collapse
@backstabz0r for screen flickering pls refer to my earlier ans and for your problem which you got warning message thats common warning you get when you have put phone in charge and if you using it for gaming which consumpts more nergy then, message will be" battery consumption is more then the supply"
so suggest ou to let battery get charged till 30 % and then use it for gaming or any other apps
I've read a few threads here regarding the flicker and it seems some people are confusing flicker with something that I really don't know what to call.
Flicker for me is when there's a stroboscope-ish effect, like when you place your sight just above an old CRT monitor, or when a fluorescent light is on it's last breath. Not when what you see on the screen makes random movements a few pixels in any direction.
I have flicker on my HOX. But it's only noticeable on lower brightness levels. This happens in all applications and in settings menu, everything with white or light grey background, so not related to badly written apps. But I wonder if this really CAN be software related? Has this happened with other models from various manufacturers?
mertzi said:
I've read a few threads here regarding the flicker and it seems some people are confusing flicker with something that I really don't know what to call.
Flicker for me is when there's a stroboscope-ish effect, like when you place your sight just above an old CRT monitor, or when a fluorescent light is on it's last breath. Not when what you see on the screen makes random movements a few pixels in any direction.
I have flicker on my HOX. But it's only noticeable on lower brightness levels. This happens in all applications and in settings menu, everything with white or light grey background, so not related to badly written apps. But I wonder if this really CAN be software related? Has this happened with other models from various manufacturers?
Click to expand...
Click to collapse
I've got what your describing quite a few users have. I believe it could be down to the drivers for the Soc. Might just need a driver update. Only the next update we can tell if this fixes the issue or not. We need to pressure HTC regarding this issue.
nikzDHD said:
I've got what your describing quite a few users have. I believe it could be down to the drivers for the Soc. Might just need a driver update. Only the next update we can tell if this fixes the issue or not. We need to pressure HTC regarding this issue.
Click to expand...
Click to collapse
But is it really possible that a driver issue can cause flicker? I've never seen it before.
I tweeted @htcdev earlier today about it but no response yet. I wonder what the best way to make htc aware of this is. Contacting their lousy customer support feels pointless, it won't reach the people who actually can make an impact.
mertzi said:
I've read a few threads here regarding the flicker and it seems some people are confusing flicker with something that I really don't know what to call.
Flicker for me is when there's a stroboscope-ish effect, like when you place your sight just above an old CRT monitor, or when a fluorescent light is on it's last breath. Not when what you see on the screen makes random movements a few pixels in any direction.
I have flicker on my HOX. But it's only noticeable on lower brightness levels. This happens in all applications and in settings menu, everything with white or light grey background, so not related to badly written apps. But I wonder if this really CAN be software related? Has this happened with other models from various manufacturers?
Click to expand...
Click to collapse
This is what I have, but its far worse on higher brightness levels.
Sent from my HTC One X using XDA
Right guys untick animations in Developer options, restart give it a while, go into camera you'll notice glitches, play a YouTube video you'll notice green bar on the left hand side of the screen in full screen mode. Untick animations and this disappears. It's worrying not sure what to do now.
Edit: can't repeat this but will keep trying as something did trigger it off for the screen to go like that.
Yeah, with flicker I didn't mean anything like having low fps when scrolling through stuff. I meant a quite noticable fluctuation in the brightness of the backlight if that makes sense. It is indeed quite like a CRT monitor with a low refresh rate. I haven't seen it yet when my screen brightness was high, but I'm not sure if it doesn't occur on higher brightness settings. It is also not constantly flickering, It only seems to act up when my mobile data connection is active, although I have seen a very slight flickering with data turned off. I really hope this isn't a hardware issue, the rest of my phone is pretty much perfect and I'd rather not send it in for a replacement after all the trouble I had with my sensation :/
I have the flicker issue, the screen flickers near the center a little bit to the right though, and it is reall irratating, but i can only see it when viewing pictures and on greys.
I hope it isn't hardware!!
tried all the ideas given to stop it but none work for me, still seems to flicker
Me too
I have the screen flickering too.
Im reluctant to return it as apart from this the handset is solid.
It on appears on certain colours making me think its software related.
I also have the exact same flicking issue. From what I have heard it is a software issue rather than a hardware issue. Just to be on the safeside though I am returning my One X to Phones4U for a replacement. Will be interesting to see if the replacement has the same issue.
I made a thorough check yesterday. I downloaded a brightness control app where you can write what brightness level you want so i tried from 3% which was the lowest possible step by step up to 15%. At 15 the flicker stops so its not 30 as I said before. this is my only issue too so I dont dare to replace it just to get a worse phone. My sister is getting one next week so gonna compare them.
Sent from my HTC One X using XDA
I noticed this too, but i believe its a software issue only. When I unlock the phone, the screen flickers while sense runs and the three menu button appears then goes. Once its all settled its fine. I believe this is to do with sense rather than a phone issue, and will be addressed via OTA.
nickp123 said:
I noticed this too, but i believe its a software issue only. When I unlock the phone, the screen flickers while sense runs and the three menu button appears then goes. Once its all settled its fine. I believe this is to do with sense rather than a phone issue, and will be addressed via OTA.
Click to expand...
Click to collapse
Not so sure about it being a specific Sense issue as I have noticed the screen flicking in 3rd party apps such as Spotify.
has anyone had theirs replaced yet? this is doing my head in! really noticeable on a grey background
johnbhoy89 said:
has anyone had theirs replaced yet? this is doing my head in! really noticeable on a grey background
Click to expand...
Click to collapse
Phones4U are sending me out a bag to send it back so hopefully should have a replacement by Monday or Tuesday.
dr9722 said:
Phones4U are sending me out a bag to send it back so hopefully should have a replacement by Monday or Tuesday.
Click to expand...
Click to collapse
I phoned dialaphone there, i made them aware of the problem with my phone, told them if it wasnt fixed with the update then I would like to replace my phone, told me I had until next tuesday to see if its fixed, until I reminded her about distance selling regulations which gives me 28 days from receiving the handset.
johnbhoy89 said:
I phoned dialaphone there, i made them aware of the problem with my phone, told them if it wasnt fixed with the update then I would like to replace my phone, told me I had until next tuesday to see if its fixed, until I reminded her about distance selling regulations which gives me 28 days from receiving the handset.
Click to expand...
Click to collapse
You do indeed have 28 days to return your phone however I wouldn't count on HTC releasing an update before then
Hi all, I am on my second device but had up until now never experienced screen flicker at all.
I open up power settings, click on the graph at the top and I can see a the graph kind of lightly pulsating/flickering. I've tried it on fixed brightness levels and automatic and seems to do it on both.
Anyone else able to test it and see if they see it too ?
mgdew said:
Hi all, I am on my second device but had up until now never experienced screen flicker at all.
I open up power settings, click on the graph at the top and I can see a the graph kind of lightly pulsating/flickering. I've tried it on fixed brightness levels and automatic and seems to do it on both.
Anyone else able to test it and see if they see it too ?
Click to expand...
Click to collapse
Not having a go but why have you opened a new thread for this when there are loads already?
mgdew said:
Hi all, I am on my second device but had up until now never experienced screen flicker at all.
I open up power settings, click on the graph at the top and I can see a the graph kind of lightly pulsating/flickering. I've tried it on fixed brightness levels and automatic and seems to do it on both.
Anyone else able to test it and see if they see it too ?
Click to expand...
Click to collapse
Tried it on low to high and auto.Not a single flicker.
Sent from my Transformer Prime TF201 using xda premium
cjm1979 said:
Not having a go but why have you opened a new thread for this when there are loads already?
Click to expand...
Click to collapse
because I am not convinced what I am seeing is what others are describing in the other threads as screen flicker, hence why I described it.
If its not appropriate then feel free to get someone to delete the thread.
No flicker here, HT245
Sent from my HTC One X using xda premium
I'm on an HT23 device, bizarre, I've asked a couple of colleagues here at work to check it and make sure its not my eyes playing tricks on me.
Nothing on my HT23.
Before this gets closed.......I'm convinced not everyone can see the flicker and those who can may well experience it to different extents.
Sadly, I can see the flicker of DLP projectors all also know as "the rainbow effect" whereas many others cannot.....
flicker may not be the correct term, its like a really minimal strobe effect, its like the voltage to the brightness is being constantly altered by a couple of percent rapidly.
It's visible on my phone by myself and some colleagues using 50% brightness fixed and auto
and as I said in post 3, if people think this should be in another thread, or I have violated any rules and annoyed people please feel free to get a moderator etc to delete the thread.
mgdew said:
flicker may not be the correct term, its like a really minimal strobe effect, its like the voltage to the brightness is being constantly altered by a couple of percent rapidly.
It's visible on my phone by myself and some colleagues using 50% brightness fixed and auto
Click to expand...
Click to collapse
I have provided test cases for how to reproduce this kind of flicker before. Today I reviewed another two HOXes of colleagues and so far I have not found a single HOX that I cannot make flicker. I know some are defiantly stating their phone doesn't do it. Maybe there is one out there. But I am now up to 8 phones that I have made flicker and I have yet to be shown one I cannot get to do it!
However, all of them require the battery level to be below 50% to make it reliably happen.
And yes, my wife insists she cannot see the flicker...so not everyone may realise/see it anyway.
There are 2 huge threads about the same thing btw, screen flickering...
I have the exact same thing also. It's not only in the battery menu but sometimes when i'm viewing pics, on screen with grey color is dominant it is visible more but i am used to living with that already since it's a known bug and software related, it is going to be fixed for sure in the upcoming updates. And yes, my wife and some of my friends can also see it happening, the strobe effect, trembling kind of thingy that is hard to explain.
jonstatt said:
I have provided test cases for how to reproduce this kind of flicker before. Today I reviewed another two HOXes of colleagues and so far I have not found a single HOX that I cannot make flicker. I know some are defiantly stating their phone doesn't do it. Maybe there is one out there. But I am now up to 8 phones that I have made flicker and I have yet to be shown one I cannot get to do it!
However, all of them require the battery level to be below 50% to make it reliably happen.
And yes, my wife insists she cannot see the flicker...so not everyone may realise/see it anyway.
Click to expand...
Click to collapse
just fyi, i went through 4 phones, all flickered, then 5th and 6th didn't flicker at all. so there are some out there that genuinely don't flicker.
I see it too. As if the refresh rate isn't correctly set.
http://forum.xda-developers.com/showthread.php?t=1617009
Keep it in there.
http://forum.xda-developers.com/showthread.php?t=1597448
Or here.
Sent from my HTC One X using xda premium
There are two components to what people are referring to as "flickering."
1) Nvidia PRISM controls (or tries to) the backlight to save energy.
NVIDIA PRISM Display Technology - PRISM (or Pixel Rendering Intensity and Saturation Management) reduces a mobile device’s backlight power while simultaneously enhancing the pixel color to deliver the same visual quality with substantially extended battery life.
It's more noticeable than it should be and is an issue on the Asus Prime also. We may have to live with it in some form.
http://forum.xda-developers.com/showthread.php?t=1542367
2) Graphics issues including "flickering," task bar corruption, funky appearance of the camera app and others are related to the Teg3 graphics drivers which are supplied by Nvidia. HTC acknowledged in the thread this should have been posted in that they identified the problem on May 2 and an update (not 1.29) was forthcoming. The Prime experienced this too and it took multiple updates to resolve. Let's hope Nvidia/HTC gets it right in one shot.
twistedh said:
http://forum.xda-developers.com/showthread.php?t=1617009
Keep it in there.
http://forum.xda-developers.com/showthread.php?t=1597448
Or here.
Sent from my HTC One X using xda premium
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Thanks for the reply. Like I have said twice happy for someone to delete or lock this thread if it's not appropriate.
Sent from my HTC One X using Tapatalk 2
Closed, redundant
Please read and search before posting
Hello folks,
I have had my Note 2 for a couple of days now and almost immediately noticed something strange. There is a VERY subtle flickering of the white and light grey areas of the screen. A very high frequency flicker, almost like I can see the refresh rate of the screen. My initial suspicion was that the refresh rate was lower than 60hz. So, I downloaded the app called Android System Info, and sure enough, under display, it was being reported that the refresh rate of the screen is 58hz. I got another friend with a Note 2 to confirm the same thing. My GS3 reports 60hz, and so does my friends HTC One S. So my question is, why is the refresh rate on the Note 2 not 60hz? Is this an intrinsic hardware limitation? Or can this be changed with software? My eyes can definitely notice the 2 less frames per second, I was using a GS3 since June, and switching to the Note, I immediately noticed the refresh rate was lower. Why? This is very strange to me. There are many videos on YouTube with the Note 2 and GS3 on the screen at the same time, and sometimes there is banding interference on one phone and not the other, meaning obviously the phones are running different refresh rates. Now I know the Note 2 refresh rate is lower, why? And is there anyway to change it with software?
Thanks much!
first, i think u should get yr note2 to warranty,
second, u sure yr eyes can differentiate 58hz and 60hz......?
emprize said:
first, i think u should get yr note2 to warranty,
second, u sure yr eyes can differentiate 58hz and 60hz......?
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It is EXTREMELY subtle, almost a non issue, so I doubt warranty will even say anything is wrong. I can notice it on all the demo models i've seen, so I doubt it has anything to do with my phone.
I have confirmed on 3 different Note 2s, the reported refresh rate in the app 'Android System Info' is 58hz. While all other phones I have used report 60hz.
I just find this so strange that maybe someone has a great explanation as to why this is the case. And maybe someone can dig deeper than I can and figure out if this is in the OS or an intrinsically hardware thing. I wish I had the email of a Samsung engineer who worked on the design of this phone, would love their take on why this is the case. 58hz is just such a strange refresh rate.
Goontron said:
It is EXTREMELY subtle, almost a non issue, so I doubt warranty will even say anything is wrong. I can notice it on all the demo models i've seen, so I doubt it has anything to do with my phone.
I have confirmed on 3 different Note 2s, the reported refresh rate in the app 'Android System Info' is 58hz. While all other phones I have used report 60hz.
I just find this so strange that maybe someone has a great explanation as to why this is the case. And maybe someone can dig deeper than I can and figure out if this is in the OS or an intrinsically hardware thing. I wish I had the email of a Samsung engineer who worked on the design of this phone, would love their take on why this is the case. 58hz is just such a strange refresh rate.
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you are the man, mate, my eyes cant even differentiate 50 and 60 Hz, for all my note2 experience, i cant see any unusual on the screen.
But for the 58hz issue, i think its not quite a strange thing for me, it reminds me when i was using CRT monitor(or early lcd?), it always can set the refresh rate to 58hz or 60hz, but it might like u say a hardware or driver problem, hope u can contact with samsung engineer and tell us the answer
I suppose the app might be reading the values of somewhere not actually measuring it or something ! Correct me if am wrong .
this is interesting. i also notice a subtle flicker of the screen. it's annoying in some lighting. i don't notice it on other phones.. it's definitely seems like the refresh rate is a bit slower than it should be.
The refresh rate is correlated with the resolution and the main base clock which feeds the display controller, in this case 1280 * 720 * 58Hz = ~54Mhz plus some margins for which are too long to describe, which gives them a target frequency of about 54MHz for a 16 divider of the 880MHz base clock. That's the main reason of the 58 vs 60 Hz difference.
But the reason you're seeing flickering might be completely unrelated to that and caused by some odd much lower timings in the display settings. Maybe a developer with the device could test it out by changing them.
AndreiLux said:
The refresh rate is correlated with the resolution and the main base clock which feeds the display controller, in this case 1280 * 720 * 58Hz = ~54Mhz plus some margins for which are too long to describe, which gives them a target frequency of about 54MHz for a 16 divider of the 880MHz base clock. That's the main reason of the 58 vs 60 Hz difference.
But the reason you're seeing flickering might be completely unrelated to that and caused by some odd much lower timings in the display settings. Maybe a developer with the device could test it out by changing them.
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Thanks for that information, it's great technical info I've been looking for. So it's basically a ratio/multiplier of some clock speed in the hardware. But now my question is, why would the Note 2 be any different than a GS3? I would think they have relatively the same hardware, and resolution on both screens is the same, so why would the refresh rates differ? Just seems to me that 58hz is not an ideal refresh rate. I mean, the main reason there is a trend towards 120hz TVs these days is because both movies (24 fps) and TV (30 fps) are evenly divisible into 120. Whereas with a 60hz TV, there is a remainder on 24, so movies do not interpolate as smoothly. With 58hz, no recorded content I can think of divides evenly into it, always making interpolation less smooth. Again, in my mind, 58hz is just silly, why not just give me the extra 2hz!! Doesn't make sense to me.
Final question. Would there be any way with software to change the refresh rate? Or is this set in stone at the hardware level?
I have an issue with this as well - I'm getting either fairly heavy frame skipping in any 8 or 16 bit emulator with frame skipping set to auto, or sound skipping with frame skipping turned off. I suspect this is because of the odd refresh rate with the app expecting 60hz and only running at 58 in reality, causing either the video or audio to run out of sync and needing to skip the two frames here and there to catch up. If the emulators could slow down the audio speed to match the slower video speed, it wouldn't be an issue.... but this shouldn't be the problem of the emu authors.
This happens with no other applications installed on a brand new phone. I've also installed clean rom and perseus kernel, no change. Power settings are all off, nothing is hitting my CPU to cause the frameskipping and it's very consistent, which leans towards the refresh rate causing the issues. Anyone know anything more about this? What a pain...
I am a traffic cop and I can definitely tell the difference between a car going 58mph and one going 60mph.
Sent from my GT-N7100
@rbiter said:
I am a traffic cop and I can definitely tell the difference between a car going 58mph and one going 60mph.
Sent from my GT-N7100
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I'm a noob and I don't know what "stuttering" is
But seriously, it's not like a mobile device should be able to emulate another system anyway, am i rite? Just use it for phone calls and internet browsing...
i think the reason why the refresh rate between gs3 and note2 is different due to both are using different lcd even though some of the hardware is the same.
even though the diff is small but it still incur some major hiccup where the frame skip especially with project butter where they keep the ui at 60fps.
maybe we can email to samsung engineer and they can take a look at it.
Hi all!
Does anybody know if HTC 10 uses PWM (Pulse-width modulation) for brightness control?
PWM is a cheap and easy technology to manage screen brightness. To adjust brightness PWM-controller rapidly (usually with speed of 230-240 Hz) turns backlight on and off, which in turn could cause headaches and eye fatigue after using the device.
More about PWM: https://en.wikipedia.org/wiki/Pulse-width_modulation
Absence of PWM is one of the key parameters for me. Unfortunately only a few reviewers test flickering and this information is very hard to find. So far, I have not found a single review with PWM test.
Thank you!
21.05.2016 update: Notebookcheck confirmed that HTC 10 is flicker free!
Surely the only way to dim LEDs is with PWM?
Nope, PWM is just the cheapest an the easiest way. Plus controller won't overheat.
But there are other ways to dim LEDs. One of the oldest ways - variable resistor.
Considering humans see appx 60-90 hz I'd say this is a non-concern.
Unless you're a mutant who can see 100hz+ in which case you must go crazy anywhere you go from the constant exposure to higher frequencies.
Sent from my HTC One using Tapatalk
Considering that I had 5 laser eye surgeries this concerns me a lot.
Using a screen with PWM for more that 15 minutes causes eye strain for me. And this is the main reason why I haven't already bought Galaxy S7.
You are lucky that PWM doesn't affect your eye, and probably should google further more: https://www.google.ru/?#safe=off&q=pwm+eye+strain
datafoo said:
Considering humans see appx 60-90 hz I'd say this is a non-concern.
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Where did you get that info? Especially flickering can be seen at even higher frequencies. I personally see flickering on the XPS 15 and it uses PWM at around 362 Hz.
http://www.notebookcheck.net/Dell-XPS-15-2016-9550-InfinityEdge-Notebook-Review.156354.0.html
It's not disturbing but it is noticeable.
http://www.100fps.com/how_many_frames_can_humans_see.htm
Also the difference between 60 Hz and 144 Hz in a monitor is obvious just by dragging windows around.
If you can't see it, fine. But don't go around telling untrue stuff please.
Dr. lele said:
Where did you get that info? Especially flickering can be seen at even higher frequencies. I personally see flickering on the XPS 15 and it uses PWM at around 362 Hz.
http://www.notebookcheck.net/Dell-XPS-15-2016-9550-InfinityEdge-Notebook-Review.156354.0.html
It's not disturbing but it is noticeable.
http://www.100fps.com/how_many_frames_can_humans_see.htm
Also the difference between 60 Hz and 144 Hz in a monitor is obvious just by dragging windows around.
If you can't see it, fine. But don't go around telling untrue stuff please.
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Untrue stuff LOLOLOLOLOL - I believe you're suffering a nocebo effect.
Pardon my incredulity but as I mentioned if you see anything over 100hz you're a mutant (I said 60-90hz) and that appears to be corroborated by your 100fps link. I'm not completely disagreeing with you, I'm however pointing out that you're such a small subset of the population it's rare and hard to validate.
Although FPS and HZ are different we'll bypass the semantics for the fact we're discussing cycles per second in a general fashion.
It must drive you crazy being ANYWHERE with lighting and electricity. At least here in the US electricity runs at appx 60hz so lights (most computer monitors etc) must bother you quite a bit.
Either way, good luck to you. I hope you find what you're looking for.
There is of course a difference between the way LCDs refresh their content and the way CRTs did. Strobing of light can definitely be seen at much higher rates than you said.
Also I never said that it's infuriating or drives me crazy I just said it's noticeable. I have no idea where you get this from.
Tests with Air force pilots have shown, that they could identify the plane on a flashed picture that was flashed only for 1/220th of a second.
That is identifying. So it's pretty safe to say, that recognizing, that SOME light was there is possible with 1/300th of a second.
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That was the part I wanted to show you.
Now the blur on LCDs is a different story, since the lights are on constantly and only the pixels change color at the given rate. But still you cann see the motion blur / dragging of the cursor even on a 144 Hz screen. Albeit much less noticeable than on a 60 Hz one.
If given a 60 Hz display side by side with a 144 Hz panel most people will be able to tell you which one feels more natural.
BTT: I don' think it will be a real poblem even if HTC does use a PWM module. Even though it might be somehow noticeable it won't disturb most people. Also: how often do you use your phone at the lowet brightness.
Yay! HTC 10 is PWM (flicker) free! Confirmed by Notebookcheck: http://www.notebookcheck.com/Test-HTC-10-Smartphone.164311.0.html (in German).
Oscillogram: http://www.notebookcheck.com/fileadmin/Notebooks/HTC/10/response_pwm.jpg
Just want to add that being able to notice it and it affecting you are two different things. Normally you can't notice neon lights flicker but they do and it will strain your eyes and make you tired. That's why bars have started to charge them out to leds.
Sent from my HTC 10
Glad I'm not effected by this crap. I'd hate having to pass on phones I really like just because they use PWM.
Sent from my SM-G935T using Tapatalk
Hi, is this issue still a problem? After some time during gaming you are not able to get the backlight over 50% like on this video:
Dimming
Or it have been solved by the latest updates and you are able to set maximum brightness even after half of an hour of gaming?
I think the dimming issue has been significantly reduced and fixed with the latest firmware.
It still dims but not by much, you might not even notice it at all depending on how much you're into the game or how sensitive your eyes are to light change.
Dimming is fine for me. I think its really feature not an issue for thermal purposes.
I'm more worried in touch delay issue. They marketed this device with high touch response and how come it would have an issue in the hands of customers.
Two words: Android 11.