I'm experiencing either a defect or an unfortunate feature on this tablet. I just took delivery of a new one, and while viewing any solid colors besides grey on the screen everything is fine (also no dead pixels), but I'm noticing what appears to be slight backlight flickering/pulsing whenever grey or light blue is shown on the screen. It seems to be PWM (pulse width modulation) of the leds, but I can't be certain it's a defect or just the unfortunate way these tablets' led screens are designed. It's a very subtle but consistent and annoying pulse, but it's definitely there. Can anyone confirm that PWM is what's going on with these tablets or if this is a defective screen. The screen doesn't pulse at all on any other colors solid or only partially filling the screen or otherwise.
I haven't noticed anything on mine, though I tend to keep the backlight fairly low (17%).
One thought though which is why I'm saying anything, I remember on the nexus 7 there was an issue with one of the friction pins not connecting to the back of the case's antenna fully sometimes, which would cause the radio/wifi to suck extra power resulting in backlight pulses... have you tried turning on airplane mode (disable the cellular) with wifi off to see if that makes a difference? Though it would be odd if it only affected the one colour... I suppose it could be your ambient light source too, does it do it in sunlight?
One thought though which is why I'm saying anything, I remember on the nexus 7 there was an issue with one of the friction pins not connecting to the back of the case's antenna fully sometimes, which would cause the radio/wifi to suck extra power resulting in backlight pulses... have you tried turning on airplane mode (disable the cellular) with wifi off to see if that makes a difference? Though it would be odd if it only affected the one colour... I suppose it could be your ambient light source too, does it do it in sunlight?
Good idea! Unfortunately, killing the antennas doesn't affect it. And there's no ambient light sensor on the g pad x, so that's out as well
I'm so disappointed because there are not dead pixels and only very little light bleed in the corners too.I didn't mean ambient light sensor would be the cause, more that perhaps you have bulb/s that cycle at a specific rate at a certain colour range that would cause a subtle flicker, I always found those big long roof fixture fluorescent tube lights bad for this sort of thing... I notice some "out of the corner of my eye" subtle flickering on my PC LCD when I have the one CFL on, but not when I have the other LED lamp going instead for example. I just tried a LCD screen tester with various solid colours (cyan, blue) and the only 'flickering' I'm seeing is if I actually move the screen, this panel has some waviness in it that is visible when the screen is off and you angle it just right under a light which seems to pop out on these blues with the backlight turned up - but only when the screen is physically moving. Definitely not a perfect panel, but for me nothing like what you are talking about.
I'm outta ideas though, unless you are running a custom firmware and it does something different than what my stock does.
GL
edit:/ just read that RFD post from the other thread, and I definitely notice a flicker when in nova's app drawer. It seems to occur only right after I move the tablet and only noticeable at higher backlight settings, if I set it down flat and don't move it, it doesn't do it. Perhaps related to the gyro sensor? Something not isolated fully/properly would be my guess. With the wifi turned on, it also does it along with the activity up/down arrows on the logo... now that I've seen it I wonder if its going to bother me on lower brightness levels now :silly:
I'm outta ideas though, unless you are running a custom firmware and it does something different than what my stock does.
GL
edit:/ just read that RFD post from the other thread, and I definitely notice a flicker when in nova's app drawer. It seems to occur only right after I move the tablet and only noticeable at higher backlight settings, if I set it down flat and don't move it, it doesn't do it. Perhaps related to the gyro sensor? Something not isolated fully/properly would be my guess. With the wifi turned on, it also does it along with the activity up/down arrows on the logo... now that I've seen it I wonder if its going to bother me on lower brightness levels now :silly:
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Thanks for checking. I tried the airplane mode setting, and I swear that fixed it. But then it came back after a few more toggles of data/wifi. Given that you're seeing it too and that others have reported seeing it as well in the RFD thread, I'm thinking it isn't a defect but rather poor design. There's little chance it would be this widespread and only on the exact same color combo for everyone. I think most people just never notice it since you're rarely just looking at a solid or mostly solid grey screen. I wonder if there's a way to disable the gyro on a stock/non-rooted gpad like mine? For me, it does it regardless of brightness level.
I've seen this on different devices too, so it's not just a G Pad X thing. I wanna say I've seen it on my Nexus 5 back in the day, but I've had many devices so it's hard to remember. But yep, noticed it happens on "grey" colors. It's much less noticeable with the brightness lowered. Never really bothered me so never posted about it.
My guess is it's the led pulse width modulation. It affects some screens more than others, but is an issue with led implementation on lcd screens in general. I'm leaning towards keeping the tablet as I'm 99% convinced that another unit would exhibit the exact same behavior. Glad to hear it isn't a defect, but sad that they did not manufacturer a better screen.
I don't want to clutter this thread any further, but I'm going into a B&M t-mo store to see if I can test this out on a display device to confirm how widespread this issue is.
Quick update on the flicker issue. It's a problem with all the units, or perhaps just poor design. I did a warranty exchange, and the replacement unit had the exact same issue. Oh well. Just time wasted I guess.
I have the same exact issue with the one i got my mom. Fortunately it doesn't bother her too much but it definitely seems to be a design flaw as we also returned it with the return unit having the same issue
Welcome to the world of flicker.
What you are seeing is very common and an unfortunate side effect of cheap reference designs and a don't care attitude.
There are many new standards for flicker but I doubt they'll be implemented. Flicker pwm needs to be in the 10khz range to be indistinguishable to constant current drives.
What you are seeing is very common and an unfortunate side effect of cheap reference designs and a don't care attitude.
There are many new standards for flicker but I doubt they'll be implemented. Flicker pwm needs to be in the 10khz range to be indistinguishable to constant current drives.
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