yashsingh1/xdaforums huggingface dataset:
[Nexus 7 General] YomsThe3rd:
I've received much from xda-developers forum, so I wanted to give a little back.

My Nexus 7 8GB had the flicker issue and some screen separation on the left hand side, I contacted Google and did the RMA process, yesterday I received the new one, and the change in hardware has eliminated the flicker issue. I know many people are waiting, hoping it's a software fix (and there may be one), but there is definitely some hardware change that fixed the flickering.

The panel in the new Nexus 7 seems different, as the color temperature is significantly cooler than on my original Nexus 7.

I recorded a quick video, which shows them side by side, it's hard to tell unless you're running full screen and HD, but the flickering is visible. Hopefully this helps those waiting for a software fix not get stuck with a bad screen...

Other than the flickering problem, this tablet rocks!

[YOUTUBE]VfgUmb4sOyY[/YOUTUBE]
[Nexus 7 General] kenyee:
Could you post your serial# and CSSN off the box?

Doesn't have to be your exact serial#...just a rough one. E.g., mine is 338Kish and it still has the flicker issue...
[Nexus 7 General] just lou:
What makes you so sure there's been a hardware revision?

I have one of the first N7's shipped from Google, and it's flicker free.
[Nexus 7 General] adamhlj:
Do you have the 8 or 16 gig version?
[Nexus 7 General] YomsThe3rd:
I'm not sure there's been a hardware revision at all... It could just be two batches of the panels, one faulty? Or something else. All I know is that one panel is distinctively warm in color (the original) and has the flicker issue, and the other panel is cool and with no flicker. Maybe just a bad batch of panels? Or some of the other accompanying driver hardware? Assembly?

I'm just saying that a hardware change made a major and distinct difference for me.

When I get a chance I'll post the CSSN/SN.
[Nexus 7 General] just lou:
8GB
[Nexus 7 General] spooke:
My dads Nexus 7 16gb has quite a yellow tint to the screen and the left side of the screen is sticking up - although I don't think it flickers.. He's getting a replacement tomorrow although it won't be directly from Google. (Tesco's)

I'll post up whether the screen is any different.
[Nexus 7 General] scootle74:
This is good info. Once we get more confirmation that perhaps a RMA will solve the issue, then we'll see how good Google is at doing exchanges from the Play store. This entire issue has been so hard to pin down.

It would be nice if Google was more proactive about it and just offered a solution, but that is wishful thinking, I know. :(

Thanks!

PS my SN on a 16GB model that demonstrates the flicker is:

SSN: C60KBC226---
[Nexus 7 General] adamhlj:
I just got off the phone. Was on hold for all of 2 minutes. The whole phone call was 8 minutes and 18 seconds. Hopefully it all works out.
[Nexus 7 General] gnewylliw:
heh I did the map test too and saw flicker and planning my return, but I saw some other users were saying tegra devices had this problem. so I turned OFF the wifi, and there was still flickering!

so.. before anyone jumps to conclusions maybe try the map scroll with wifi off
[Nexus 7 General] YomsThe3rd:
I had wifi on for both of them in the video, brightness set to the lowest setting, and the auto brightness checkbox off. It was happening to me in all applications, the map just seemed the easiest to reproduce in, so it may actually be related to the wifi receiving/sending data.

The new one does not have the issue at all.
[Nexus 7 General] gnewylliw:
can you try them both with wifi off?
[Nexus 7 General] wynand32:
I just got around to trying to find this issue on my Nexus 7, and I do see that the Maps app has some "flicker" (i.e., color or brightness changes). If this is what everyone is talking about (sorry, haven't kept up with this particular issue), then let me say that the EXACT same thing happened on my Transformer Prime.

I remain pretty sure that this whole issue is related to the PRISM power-saving tech that's a part of the Tegra 3 platform. I've seen too many wonky issues like this on too many Tegra 3 tablet to think it's not related (that includes the Prime, the Toshiba Excite 10, and the Toshiba Excite 7.7, the latter of which is even an AMOLED screen and so not subject to LCD-type issues).
[Nexus 7 General] Cybore:
So I tried to reproduce the flicker on my N7 and was only able to reproduce flicker upon panning in google maps. When I drag the map around and the street names are loading I can sometimes see a minimal flicker (generally when I a lot of loading is occurring). Its pretty subtle and only visible when brightness levels are low.

Don't see any flickering at any brightness level besides that.

To OP, can you see any flickering at all upon panning in your new device? my N7 doesn't flicker like the old one you have, I could probably bare with it.
[Nexus 7 General] pclov3r:
In a dark room with a Strong wifi full bars and barely and WiFi signal had the same Flickering issue with google maps. It is something else.

So for me it doesn't appear WiFi signal effects it.

Going to be calling Google tomorrow.
[Nexus 7 General] charlesky:
The change in colour temp is probably just normal variation. No mobile devices are calibrated (including the iPad3) and they all show a fairly wide variety in their white balance. It is possible, though, that the flicker has some sort of causal relationship with the screen lift.
[Nexus 7 General] GotLoveForAll:
My search led me here after noticing the flicker issue while browsing the web on my n7 at night.

I just did the map test and it flickers every 5 secs with the WiFi ON. With WiFi OFF there is no flicker. Same with all the apps that use WiFi.

So is a this a HW or SW issue?
[Nexus 7 General] SDO1000:
There's already a large thread on screen flicker. Not sure why we needed another. Maybe a mod can merge them.
[Nexus 7 General] brave83:
Thanks for the post. I received mine on Tuesday and noticed the screen flicker with the auto brightness. Called last night and they're sending me another. If the RMA flickers, I'll wait until Google's new Motorola division begins creating actual PURE Google products.

Here's my Nexus serial: xx0KBC019770
[Nexus 7 General] scratchybadger:
My first device had the screen separation issue. I have since had this replaced and the new one has the screen flicker.

It is most noticable when the brightness is at its lowest, above 20% it _almost_ disappears. turning wifi off seems to stop the flicker.

In the video did you have the brightness the same on both?
[Nexus 7 General] GotLoveForAll:
He clearly shows at the end of the video that they were both at the lowest setting with auto brightness turned off.
[Nexus 7 General] shamo42:
My screen has a quite warm color temperature. No flicker here. Did the maps test on 0% brightness.

So I don't think the flicker issue is related to the screens color temperature.
[Nexus 7 General] jaroslavj:
[YOUTUBE]lBaVxUvPtLA[/YOUTUBE]

Do you think this is flickering? Most obvious from 0:20.
[Nexus 7 General] Nascar Dog:
Yes, that's it.
[Nexus 7 General] sharp2G:
guess I'm getting another return... i really thought it would be software related..

Sent from my HTC One X
[Nexus 7 General] pmgreen:
Can someone help me understand the "map test." I must have missed it in reading this thread
[Nexus 7 General] GotLoveForAll:
Open up Brightness Control. Turn of Auto-Brightness and put Brightness on lowest setting (or 3%).

Open up the Google Map and let it load. Do not move it around. Make sure WiFi i on

Stare at the screen and it will flicker every few 3-10 seconds. If it does not, kudos to you! :)

For me it flickers every 5 seconds on Google Maps and constantly on every other App that uses WiFi. :(
[Nexus 7 General] pmgreen:
Thanks Got... I've been having the issue predominately while using an ereader app. The brightness is all the way down and would still get a flicker. Thought it was my eyes, glad to know that's not the case.

Have you requested a new unit?
[Nexus 7 General] YomsThe3rd:
As promised my serial numbers are:

Original Nexus 7 (with flicker): C60KBC115---

New Nexus 7 (no flicker): C60KBC014---

The new one is performing excellent, absolutely no flicker.

Hope this helps...
[Nexus 7 General] kenyee:
I think you're lucky. AFAIK, your "new" one is older.

My serial# is C60KBC366xxx where the last 3 digits are numbers. So to me, that means 366K Nexus7's have been created. Your working one is in the 14K range. Your bad one was in the 115K range. Mine still has flicker :(

Someone said the problem is a loose solder joint, so you might have just gotten lucky and the autosoldering equipment oversoldered a bit on yours..or you got one that has been pre-inspected :)

And again, it usually matters only if you don't have a strong wifi signal...it'll barely flicker w/ a strong wifi signal...

p.s., Ditto the two flicker threads should be merged...or one should die off...
[Nexus 7 General] GotLoveForAll:
I bought mine yesterday from Best Buy in Canada. I called them this morning and they are out of stock. They said to call every day and put one on hold when they did get them. Should be by the end of next week they said. :(

Not true. I have a Wireless N modem and am sitting less than 4 feet way from it. I have FULL WiFi signal bar strength and the problem persists. Where did you get your info from?
[Nexus 7 General] just lou:
Someone posted the theory about weak wifi on here the other day, and it immediately became "fact".
[Nexus 7 General] GotLoveForAll:
Gotta love the Interwebs. Also, now we cannot un-fact it. Because its the Interwebs. :(
[Nexus 7 General] Shano56:
no screen flicker on google maps with wifi on. running cm10. Used to see it a lot in tapatalk on stock firmware, haven't seen it in a while

S/N: 015d172c981-->
[Nexus 7 General] kenyee:
Actual usage.

I've been fighting this for a while now (first one to come up w/ the wifi theory on Android Central if you dig that thread up)...thought the first N7 was damaged by UPS because of the flickering. Now on my 3rd and the issue is barely noticeable to me w/ full wifi signal...
[Nexus 7 General] pclov3r:
they would send my information to a Specialist.

Hopefully they reply soon and hopefully the new one is fixed.
[Nexus 7 General] tevinwade:
The best I could capture. I use the Screen Filter app as a work around. Turn the brightness up to 30%, then enable the screen filter.

https://docs.google.com/open?id=0B9S8tYCHjPlIcUE1VUdTbWs2TTQ

It's screen seems to flicker every time the map has finished loading/rendering.
[Nexus 7 General] jaroslavj:
Who has flicker in other apps? I can see flicker only in google maps, not google chrome when browsing xda or reading books.

Now you might say, because you aren't downloading, to make it fair I turned on an online radio and still no flickering in chrome or moon+ or anywhere.

So like with the famous 180 bug in dead trigger, maybe GOOGLE MAPS is buggy?

If you google: "google maps flickering android" you get results like this http://code.google.com/p/osmdroid/issues/detail?id=207 which support my theory.
[Nexus 7 General] tevinwade:
The screen flickers in other apps too; it's just more noticeable in Maps. It flickers in every app with a brightness level of at most 25% with WiFi on
[Nexus 7 General] GotLoveForAll:
I have flicker is all apps that use WiFi. :(
[Nexus 7 General] gnewylliw:
Make sure you try the test with WiFi off too! Apparently tegra devices all have a small flicker on maps, and other apps that use scrolling. If you don't see the flicker while loading chrome pages, you should get suspicious.
[Nexus 7 General] jaroslavj:
I get only very slight flicker when scrolling/zooming in(when it is still there is no flicker, still when streaming radio = no flicker). Doesn't matter wifi on or off. Also I wouldn't call it flicker more like brightness change.
[Nexus 7 General] mi7chy:
Apps that only use WIFI are not affected. Flicker appears when both WIFI and GPS are active such as Maps, Google Now when it's pulling GPS location, etc.

Most people will not notice because when they use GPS they're using outdoors where brightness isn't low and they're out of range of WIFI.
[Nexus 7 General] SDO1000:
I haven't had my gps on the entire time and flicker has been an issue. This is the first time I've heard anything about gps being related.
[Nexus 7 General] just lou:
Of course. A new day. A new theory. :rolleyes:
[Nexus 7 General] driscollw:
was halletec

I turned off all my location services in settings, turned my auto brightness off and put my brightness at 0 and my flickering stopped. I experienced flickering when using chrome and reading books. I only used my tablet for 10 minutes after making these changes and didn't notice it anymore. I will do another hour reading session tonight and report to you guys. YMMV
[Nexus 7 General] R3dbeaver:
my 8Gb is perfect too.
[Nexus 7 General] dansan382:
i get my flicker on any app... ive decided against using auto brightness because i feel its too dark so i usually run like 30% or so.

i bought mine from gamestop, also had some screen lifting on left side so not sure if i'd have to deal with gamestop or go directly to google.
[Nexus 7 General] MikeMurphy:
So, apparently the "flicker" is really just a subtle dip in brightness.

^ hopefully this clears it up for those trying to figure it out.

---------- Post added at 03:06 PM ---------- Previous post was at 03:02 PM ----------

I'm actually glad I'm not the only one with these problems. Initially I thought my eyes were playing tricks on me.

Has anyone determined whether the problem exists while the unit is plugged in?
[Nexus 7 General] JaSauders:
I have it in mine (Staples 16GB Nexus 7) as well. I notice it in almost any app that has a white background. I remember seeing it on Facebook before. I also noticed it on the Currents app as it was loading at one point. It doesn't really bother me since it's only noticable at 0 brightness. Once I bump it up 2 or 3 notches I don't see it at all.

I've been reading a lot about this "is it software or hardware" story, and I'm still not sure what to believe here. I find it confusing that a new RMA'd tablet fixes it, because as I understand it... there's been no hardware revision... if there's no hardware revision, how was it "fixed"?? Likewise, if it is a soldering issue, then I suppose every tablet that was made with the Tegra 3 has manufacturing flaws? :confused::confused::confused:

I suppose anything is possible, but I can't help but to still think it has to be software related somehow.

Fun thought: Has anybody done a factory reset on their Nexus 7? Has the flickering occured after the reset? Anybody running a custom ROM and still experiencing the issue?
[Nexus 7 General] scratchybadger:
I don't think it's a software issue. The first Nexus 7 I had (with the left side screen lift issue) did not have an issue with flickering at all. The replacement does, even after a factory reset. If it was software it should do it on all stock devices which it does not appear to do.

My belief is that it is a hardware problem, we do not see the issue on all devices because when you start getting into the physical there are opportunities for quality control and production consistency to waver.
[Nexus 7 General] schwenn:
It is software problem, was the same with the one X. They solved it via firmware upgrade. Seems to be a Tegra related thing.

edit: or it is a hardware problem which can be fixed by firmware..
[Nexus 7 General] MikeMurphy:
I think I can offer a sound hypothesis as to what's happening here, and it's not exactly a problem with the screen itself. Read my post in it's entirety.

The GPS module consumes quite a bit of power, and the WiFi consumes about half what the GPS consumes. Activated together (ie, maps), and in conjunction with momentary high CPU usage when Maps renders after user input, the backlight becomes starved for power. But why?

Obviously the N7 is capable of consuming much more power, ie screen brightness at max. But the problem I suspect is power management policies, which may be a bit too aggressive or poorly calibrated. Perhaps Maps so readily shows the problem because it's highly threaded and able to suddenly load up all 4 CPU cores causing a slight uncorrected voltage 'droop' to the screen.

The reason different screens react differently is simply because each batch of screens will have very slight differences in tolerances, of which those slight differences are most evident at lowest brightness. Some backlights will dim during a very slight power dip, others will not, even when exposed to the exact same power dip.

Faulty screen? Not really as the drop may be way out of spec. The backlight is a 'dumb' component that converts the power given to it into light. If the screen dims its because the power sent to it has been reduced, and some are affected more becausethere are slight variations in tolerances of the backlights depending on the batch.

More likely the problem really comes from a poorly calibrated power distributing mechanism / policy, that under-powers the screen ever so slightly under very particular circumstances.

Hence why people see this unusual change of brightness, aka "flicker" at lowest brightness setting.

Is it fixable via software update? I think it is, but I'm not intimately familiar with the firmware.
[Nexus 7 General] JaSauders:
I hear ya. But I've also seen some Nvidia chipsets act up on Ubuntu machines using the same driver that don't exist with other identical setups using the same Ubuntu version and the same Nvidia driver. Yet, a driver update fixes said issue.

There's so many things that are contradictory. Neither side is more logical than the other. We're all executing identical Android code, no? So why would it be software if everything is identical? In that instance, it almost has to be hardware. That said, how is it possible if other Tegra 3 based devices experienced the same issue, some of which that was fixed with a software update?

*head explodes*

If I knew the next Nexus 7 would be screen flicker-free and if it was truly a hardware issue, I'd RMA mine right now, but I'm still a little hesitant because WHAT IF it happens to be a software issue updated in the next release?
[Nexus 7 General] YomsThe3rd:
This could be it, different batches of panels, different tolerances... But the replacement I received has not shown any flicker at all, whereas the original one would constantly do it.

Maybe I'm paranoid, but I'd rather get new hardware than cross my fingers and hope that a firmware/software update will fix it in the future...
[Nexus 7 General] KARNAG3:
ghosting issue

In hope that the flicker problem would be solve with a brand new unit, I went to futureshop to exchange it. Maybe the flicker problem doesnt seem to be a issue now but unfortunately, the reported ghosting issue as now come up on the new unit. On the background and I can clearly see the ghost of the Google Play widget items when changing panels. If I open a ebook and let it open for a few seconds, all the text will still be visible in the background when returning to the main desktop. I'll return it and wait for a new units...Its really sad because I freaking lovvvvee the Nexus 7!!!! :(
[Nexus 7 General] matthewr87:
Man, I've already returned 3 tablets because they had bad screen lift. I bet that when I finally get one without screen lift it will either have the screen flickering issue or the ghosting issue and I'll have to return it as well. Guess some things just weren't meant to be lol
[Nexus 7 General] gerrylum:
Yup... I've got it too.

I'm here to chime in on having the flicker issue as well. I think I've been subconsciously noticing it since I got it last Friday, but I *defintely* noticed it last night while reading in bed in a dark room.

Was occurring while using any app with autobrightness on and full WI-FI signal, and only occurred when WI-FI was transmitting. The flicker was so bad I had to stop reading and put the N7 away as I was getting a bit of a headache. That flicker can't be good for your eyes.

I'm hoping it's something they can fix with an OTA update... but I'm waiting to see if there's more of a consensus about whether the new batch of N7s fix the problem or not. If so, I may just exchange it.
[Nexus 7 General] JaSauders:
Only occurred when wifi was transmitting... huh? I wonder if that's food for thought. I talked to my buddy and he said his MacBook pro does this very thing as well. I wonder if the wifi transmitting is continuously requiring different bursts of energy instantaneously, sort of like having a massive sound system in your car and watching the lights dim under hits from low end bass...

I assume those users out there who seem to have gotten fixed tried after rma'ing the device have repeated these exact steps to see if it's there?

EDIT - Well, Google said they cannot return my device as I bought it at Staples (guess I didn't think of that when I called Google). With Staples, I'm on day 13 of the 14 day return policy. Likewise, Google just got 16GB variants in stock on the play store. Since Asus was of little help when I called them (up to a 14 day turn around for a new device - really?), and considering Staples is out of stock (they can return it - just can't replace it) I think I may return it at Staples and turn around and order a new one on the play store through Google. I'd rather take advantage of the local-return capability I have now instead of having to deal with Asus and their lackluster replacement policy down the line. This is a little more food for thought on why it may be nice to have ordered through the play store... even if the preorders were handled backwards.
[Nexus 7 General] kenyee:
FWIW, I tried w/ GPS turned off and I still see flicker w/ low signal quality wifi....seems to flicker less though. I'm still guessing power issue...I don't understand how a loose solder connection could behave this way...

p.s., and I did a factory reset when I first got it...flicker still happened while setting apps up. The whole reset thing is a weird thing Google Play support asks you to do...
[Nexus 7 General] potentiality:
Look this has been gone over. Its not a software issue. Did you all claiming this even bother to look at the YouTube video showing the difference? If it was software all units would be suffering from it no matter the build revision.

On topic

flickering unit:

015d1664b52****

C60kbc19****

New unit from playstore...STILL FLICKERING

015d262e961f****

C70kbc08****
[Nexus 7 General] h00py:
If anyone has 2 units where one has flicker but the other doesn't you could pull the last_kmsg and see if the panel_id or panel_vendor is different between units. This should show if there's been a hardware revision?
[Nexus 7 General] hafai:
Interesting. I don't know what the ssn of my original was as it has already been returned but my new one, which had a loose spot that was easily fixed with an overnight clamping, is one of the C70KBC08****'s. And it has no screen flicker. The display deems a bit warm so I don't think there was a hardware change as the number on mine is "after" the numbers of what the op's.
[Nexus 7 General] Arthur Hucksake:
Two One Xs that I had, flickered slightly.

And i'm on my third Nexus 7 , all three of those had it to some extent.

The third one it's hardly noticeable.

There is something cranky on the Tegra SoC going on. I wouldn't say it was hardware, but more a case of how the software handles it.

To me it almost feels like a refresh rate issue.
[Nexus 7 General] MattSkeet:
I'm on my second nexus 7 and this one has a very tiny flicker once in a while ... however I'm not returning it just yet ... I'll live with it for couple of months and will send it straight to Asus ...

I'm hoping that after that time they will either have a new revised units or solution to the problem .... exchanging for a new one is like playing lottery ... if you don't have a flicker than you might get dead pixels or screen lift or light bleeds ....

This is what I always used to do with my hardware if something like that happened on a bigger scale just wait till they manufacture better model and than send it ...