Wasabi Mango Zen U400

jthom127:

Reading the thread on the WM UHD400, I came across a better test for PWM issues. Inversion (pixel-walk) - Lagom LCD test

My current monitor is a Dell u2713hm, which is an IPS. After resetting the monitor to its defaults, I did the test on the Lagom page ("inversion pixel-walk test"), and I can see no problems except 4A. It's a bit like going to the doctor and have your eyes tested. :)

EDIT. After testing it again, I can also see some flickering on 4B / 4A
 
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iBurgerr said:
jthom127:

Reading the thread on the WM UHD400, I came across a better test for PWM issues. Inversion (pixel-walk) - Lagom LCD test

My current monitor is a Dell u2713hm, which is an IPS. After resetting the monitor to its defaults, I did the test on the Lagom page ("inversion pixel-walk test"), and I can see no problems up to panel 7A. It's a bit like going to the doctor and have your eyes tested. :)
Click to expand...

With the monitor's default setting, I see slight flickering on 3, and with the brightness lowered to around 25, I notice flickering on both 1 and 3. All other boxes appeared normal.
 
Interesting. With the Dell u2713hm IPS, no PWM, I can see some light flickering on 4A / 4B. Actually. I was wrong before. Thanks for the report man.
 
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Frankly, the Zen U400 might be the best panel on the market right now for me. I'm planning on a multi-monitor setup and the thin bezels make it very attractive.
+ no real pwm issues
+ good screen, like the uhd 400, better than the ahm a409
+ higher quality Samsung VA
+ no protruding control panel, as on the uhd400
+ rgb, not bgr, so can be used on the Mac
+ thin bezel for multi monitor setups
+ no annoying blue leds

A user of the Mango UHD400 reported that he had terrible sound issues when he switched resolutions. Given that the Mango UHD400 is the big brother of the U400, the panel should be very similar.

"[the UHD 400 is] constantly buzzing and crackle and pop every time the monitor turns on or resolution changes." (Source)

My question was: do you also experience this problem with the U400?
 
iBurgerr said:
Frankly, the Zen U400 might be the best panel on the market right now for me. I'm planning on a multi-monitor setup and the thin bezels make it very attractive.
+ no real pwm issues
+ good screen, like the uhd 400, better than the ahm a409
+ higher quality Samsung VA
+ no protruding control panel, as on the uhd400
+ rgb, not bgr, so can be used on the Mac
+ thin bezel for multi monitor setups
+ no annoying blue leds

A user of the Mango UHD400 reported that he had terrible sound issues when he switched resolutions. Given that the Mango UHD400 is the big brother of the U400, the panel should be very similar.

"[the UHD 400 is] constantly buzzing and crackle and pop every time the monitor turns on or resolution changes." (Source)

My question was: do you also experience this problem with the U400?
Click to expand...

I have not heard any sounds at all when changing resolutions or turning it on.

There is a blue power led (that turns red when the display is off), though it is not annoying at all, as it is located just below the lower-right corner of the bezel. From a normal viewing angle (eyes just above the center of the screen), I cannot directly see the led, just a faint glow cast on to the desk below. Generally, I can't stand led lights on anything and even cut out a small piece of semitransparent tape to place over them to reduce their brightness. However, I have not had to do that on this.

Also, the screen is BGR, I'll attach a photo below, may need to zoom in a bit to see, but it does appear BGR.

6b5KpA6.jpg
 
What's better to run this at on the PC? 4:4:4 8bit, or 4:2:0 10bit?

Will there ever be a better version of HDMI 2.0 cable that would allow for 4:4:4 10bit 4k60Hz that work with the ports on this screen? Like HDMI 2.0b or whatever? Or will this tv (when used as a 4K monitor at 60Hz) forever be limited to 4:4:4 8bit?
 
WhopperMcZinger said:
What's better to run this at on the PC? 4:4:4 8bit, or 4:2:0 10bit?

Will there ever be a better version of HDMI 2.0 cable that would allow for 4:4:4 10bit 4k60Hz that work with the ports on this screen? Like HDMI 2.0b or whatever? Or will this tv (when used as a 4K monitor at 60Hz) forever be limited to 4:4:4 8bit?
Click to expand...

I run it at 4:4:4 8-bit at 60 hz. In the Nvidia control panel, I can only select 10-bit at 4:4:4 and 30hz. There is no 10-bit 4:2:0 at 60hz option, though if there were, I would still stick with 8-bit 4:4:4 for better text legibility.

As to your second question, I don't really know, but I suspect it would be forever limited to 4:4:4 8-bit as I think that is a limitation that stems from the bandwidth of the cable and HDMI ports.
 
jthom127 said:
I run it at 4:4:4 8-bit at 60 hz. In the Nvidia control panel, I can only select 10-bit at 4:4:4 and 30hz. There is no 10-bit 4:2:0 at 60hz option, though if there were, I would still stick with 8-bit 4:4:4 for better text legibility.

As to your second question, I don't really know, but I suspect it would be forever limited to 4:4:4 8-bit as I think that is a limitation that stems from the bandwidth of the cable and HDMI ports.
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Ah okay. Thanks.
 
I bit on the 40" version to replace my Seiki SE42UGT. I like the Seiki OK, but I miss 4:4:4 chroma support.... The BGR pixel arrangement is a tiny bit concerning, but really all it means is a little bit extra ClearType tuning if any difference at all.

Sounds like this will have less lag than the Seiki as well, and 40" should be the perfect size for my Ikea Jerker so my speakers will fit on either side of the monitor.

If anyone's interested I'll post some pictures of mine as it arrives and gets unboxed and setup, and my impressions as well. :)
 
NoxTek said:
The BGR pixel arrangement is a tiny bit concerning, but really all it means is a little bit extra ClearType tuning if any difference at all.
Click to expand...
What does that mean?

If anyone's interested I'll post some pictures of mine as it arrives and gets unboxed and setup, and my impressions as well. :)
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That would be cool, thanks.
 
WhopperMcZinger said:
What does that mean?.
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Traditionally on a display (be it LCD or even an old CRT) the sub pixels are arranged in RGB orientation. Windows own sub pixel font rendering engine (Cleartype) is tuned by default for RGB sub pixel arrangement. Since this display uses a BGR arrangement text rendering could look slightly wonky by default in Windows, but 30 seconds using the built in ClearType tuner in the display control panel would fix this right up. And this is only a potential issue, these days Windows might be smart enough to fix this on its own depending on what the monitor's EDID reports to the system.
 
WhopperMcZinger said:
What's better to run this at on the PC? 4:4:4 8bit, or 4:2:0 ?
Click to expand...

4:4:4 @ 60hz @ 8-bit.

I think the panel actually only supports 8-bit anyway. The literature claims support for 10-bit, but only via dithering which is pointless anyway.
 
Ordered my Zen U400 on the 4th of July and it arrived just now (the 7th). Got mine from ebay seller 'storewithstory' like someone else did earlier in the thread. I really think all of the current sellers with the U400 right now are the same exact person anyway.

The box is completely wrapped in some sort of foam. I'll unbox it tomorrow and see if it survived the trip from South Korea...
 
I have some pictures that I'll post in a bit, but my initial impressions are mixed:

The good:
1. It does indeed support full 4:4:4 chroma subsampling at 4k/60hz on all four HDMI inputs.
2. Input lag is minimal, in fact it's fantastic, at least for me. It's notably quicker than the Seiki SE42UGT it replaced as well as the two LG TVs before it.
3. Really inky dark blacks. Like the best I've seen on an LCD.

The BAD:
1. My panel has a large area of distortion on the top right quadrant... I'm talkin' HUGE. I'm hoping I can massage it out or maybe try loosening and re-tightening the screws to relieve some pressure on the LCD panel itself.
2. Response time (I'm talking pixel response time, not input lag) is abysmal. Actually the worst I've seen in awhile... EXAMPLE: Scrolling the page on the [H]ardForums by dragging the scroll bar (so you're scrolling as smooth as possible) you get tons of smearing and ghosting between the grey forum background and the black lines between sections. It seems worse the closer the colors on screen are to black. I do realize this is a known characteristic of VA panels, but my Seiki doesn't do this and it's MVA. Maybe Samsung's PVA panel is just that much different.
3. There appears to be no way to adjust the backlight. So it must be 100% all the time... so no real way to tell if it has flicker or not. I bet you anything it's adjustable in the service menu, but I haven't found a way in yet.
4. It doesn't appear to remember scaling settings between inputs.
5. Totally minor and expected, but I'll mention it anyway: The built-in speakers are atrocious. This is a given, but they're even worse than my Seiki and I didn't think it could get much worse than that. So if you ever plan to use this as a TV you'll want some sort of external audio amp and speakers for sure.


<EDIT: Pictures>


 
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After lots of fiddling around I figured out how to access the service menu. Hit the 'input' button on the remote control, then press '2580'... There is a backlight control hidden in the service menu, and it's set at 100 by default. Attempting to lower it causes the screen to start glitching like crazy though and doesn't seem to affect the actual backlight.

There are all kinds of other settings too but I'd suggest not changing what you don't understand...

 
Trying to initiate a return to the ebay seller ('storywithstory') on the basis of the distortion / splotch on the right of the screen. I've tried massaging it out, I even tried loosening and re-tightening all of the screws on back hoping that it was because some screws were over-tightened. No dice.

Honestly the pixel response time / ghosting are so bad I think I'd be sorry I bought it even if the splotch wasn't there. It's REALLY bad, like I haven't seen ghosting and smearing this bad since my first TN panel over 12 years ago. In fact it's so bad I honestly think I could capture it on camera...

Don't know how the return will go though. The seller's return policy says buyer pays for return shipping - plugging in all the details on UPS nets me two options for shipping to South Korea, both of which are over $400!
 
NoxTek said:
Trying to initiate a return to the ebay seller ('storywithstory') on the basis of the distortion / splotch on the right of the screen. I've tried massaging it out, I even tried loosening and re-tightening all of the screws on back hoping that it was because some screws were over-tightened. No dice.

Honestly the pixel response time / ghosting are so bad I think I'd be sorry I bought it even if the splotch wasn't there. It's REALLY bad, like I haven't seen ghosting and smearing this bad since my first TN panel over 12 years ago. In fact it's so bad I honestly think I could capture it on camera...

Don't know how the return will go though. The seller's return policy says buyer pays for return shipping - plugging in all the details on UPS nets me two options for shipping to South Korea, both of which are over $400!
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Damn that sucks :(

Is that ghosting thing also present in watching movies? Have you tried connecting a Blu-ray player to it yet?
 
My panel has a large area of distortion on the top right quadrant... I'm talkin' HUGE. I'm hoping I can massage it out or maybe try loosening and re-tightening the screws to relieve some pressure on the LCD panel itself.
Click to expand...
Damn. What do you mean by distortion? Do you mean like a big patch of grey when on a black screen? That must be a fault in this particular screen I would guess. Maybe it got knocked around during shipping.

Response time (I'm talking pixel response time, not input lag) is abysmal. Actually the worst I've seen in awhile... EXAMPLE: Scrolling the page on the [H]ardForums by dragging the scroll bar (so you're scrolling as smooth as possible) you get tons of smearing and ghosting between the grey forum background and the black lines between sections. It seems worse the closer the colors on screen are to black. I do realize this is a known characteristic of VA panels, but my Seiki doesn't do this and it's MVA. Maybe Samsung's PVA panel is just that much different.
Click to expand...
That doesn't sound good. If its that bad I'm surprised the others haven't mentioned it as a problem.

There appears to be no way to adjust the backlight. So it must be 100% all the time... so no real way to tell if it has flicker or not. I bet you anything it's adjustable in the service menu, but I haven't found a way in yet.
Click to expand...
What the hell? Does that mean it's always stuck at 100% brightness? I hate blinding screens at night. Will this be a problem?

Really inky dark blacks. Like the best I've seen on an LCD.
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How can that be if you said the backlight is stuck on 100%? Wouldn't that make the image all washed out and the blacks grey?
 
WhopperMcZinger said:
Damn that sucks :(

Is that ghosting thing also present in watching movies? Have you tried connecting a Blu-ray player to it yet?
Click to expand...

Yup. Even 24fps cinematic movies you can notice the ghosting effect... I'm starting to wonder if I got a genuinely bad panel or something. I could swear it's actually getting worse as time goes on...
 
WhopperMcZinger said:
Damn. What do you mean by distortion? Do you mean like a big patch of grey when on a black screen? That must be a fault in this particular screen I would guess. Maybe it got knocked around during shipping.
Click to expand...

I posted pictures of it in one of my posts in this thread, it's really visible on camera and just as visible in person.

WhopperMcZinger said:
What the hell? Does that mean it's always stuck at 100% brightness? I hate blinding screens at night. Will this be a problem?

How can that be if you said the backlight is stuck on 100%? Wouldn't that make the image all washed out and the blacks grey?
Click to expand...

The backlight is always on at 100%. My guess is this is how they get away with saying it's 'flicker-free' - even a PWM backlight will be flicker free at 100% brightness. In the service menu there is a backlight adjustment, but it doesn't actually adjust the backlight level - it just glitches out if you try lowering it. I honestly think the backlight in this set is not dimmable at all, in effect it's physically wired to run at 100% all the time.

100% backlight won't make the image all washed out and the blacks grey, not on any monitor or TV. It does make the light being emitted brighter, but it doesn't wash out colors or effect contrast. Try turning the backlight to 100 on whatever display you're using at the moment and you'll see. :)
 
NoxTek said:
I posted pictures of it in one of my posts in this thread, it's really visible on camera and just as visible in person.



The backlight is always on at 100%. My guess is this is how they get away with saying it's 'flicker-free' - even a PWM backlight will be flicker free at 100% brightness. In the service menu there is a backlight adjustment, but it doesn't actually adjust the backlight level - it just glitches out if you try lowering it. I honestly think the backlight in this set is not dimmable at all, in effect it's physically wired to run at 100% all the time.

100% backlight won't make the image all washed out and the blacks grey, not on any monitor or TV. It does make the light being emitted brighter, but it doesn't wash out colors or effect contrast. Try turning the backlight to 100 on whatever display you're using at the moment and you'll see. :)
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Both my monitor and my TV don't seem to have a backlight option. Just brightness. In fact I didn't even know about backlight settings being a thing until recently. My current monitor I have on 0 brightness due to how bright 100 is. I assume my "brightness" on my current monitor is actually just another word for backlight?

Doesn't this monitor have a brightness setting also? How do brightness and backlight differ?
 
WhopperMcZinger said:
Both my monitor and my TV don't seem to have a backlight option. Just brightness. In fact I didn't even know about backlight settings being a thing until recently. My current monitor I have on 0 brightness due to how bright 100 is. I assume my "brightness" on my current monitor is actually just another word for backlight?

Doesn't this monitor have a brightness setting also? How do brightness and backlight differ?
Click to expand...

'Brightness' is just another video processing control just like 'Contrast', 'Color', 'Tint', and 'Sharpness'. All the brightness control does is adjust the video signal sent to the LCD panel to look like it is brighter or darker. I suppose to describe it at it's most simple it adjusts how far the LCD pixels or 'crystals' will flip or open to allow the backlight to pass through. A 'backlight' control will actually adjust how much voltage is sent to the backlight and thus how bright the light actually is.

Actually to expand on that even further: Most panels don't use a variable voltage backlight and instead use PWM or Pulse Width Modulation. They run the backlight at a constant voltage but in rapid on and off pulses. By varying the duration or 'width' of the pulses they can fool our eyes into thinking the backlight is darker or brighter. This is why lots of people in the display forum are concerned with PWM backlighting, it causes 'flicker' especially at lower backlight settings and a lot of us are sensitive to it.

That may be more than you ever wanted to know about the backlight in your LCD TV / monitor. :D
 
NoxTek said:
'Brightness' is just another video processing control just like 'Contrast', 'Color', 'Tint', and 'Sharpness'. All the brightness control does is adjust the video signal sent to the LCD panel to look like it is brighter or darker. I suppose to describe it at it's most simple it adjusts how far the LCD pixels or 'crystals' will flip or open to allow the backlight to pass through. A 'backlight' control will actually adjust how much voltage is sent to the backlight and thus how bright the light actually is.

Actually to expand on that even further: Most panels don't use a variable voltage backlight and instead use PWM or Pulse Width Modulation. They run the backlight at a constant voltage but in rapid on and off pulses. By varying the duration or 'width' of the pulses they can fool our eyes into thinking the backlight is darker or brighter. This is why lots of people in the display forum are concerned with PWM backlighting, it causes 'flicker' especially at lower backlight settings and a lot of us are sensitive to it.

That may be more than you ever wanted to know about the backlight in your LCD TV / monitor.
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Haha yep. It is indeed.

So is this a problem though? Are my current monitor and TVs likely to also be stuck at 100% backlight if there is no option to change it? Would viewing a monitor with 100% backlight at night be bothersome, even with dark themes and low brightness (which I currently use anyway)?
 
WhopperMcZinger said:
Haha yep. It is indeed.

So is this a problem though? Are my current monitor and TVs likely to also be stuck at 100% backlight if there is no option to change it? Would viewing a monitor with 100% backlight at night be bothersome, even with dark themes and low brightness (which I currently use anyway)?
Click to expand...

Hmm... how can I put this... if you're used to it and don't really know anything different, then no it's not really a problem for you. :D

Me personally I do like to watch TV / movies / whatever at night and I usually turn the backlight on my display down quite a bit, to something like 30%.
 
NoxTek said:
Hmm... how can I put this... if you're used to it and don't really know anything different, then no it's not really a problem for you. :D

Me personally I do like to watch TV / movies / whatever at night and I usually turn the backlight on my display down quite a bit, to something like 30%.
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Nah what I mean is I don't know if my current screens have 100% backlight or not.
 
WhopperMcZinger said:
Nah what I mean is I don't know if my current screens have 100% backlight or not.
Click to expand...

If there is no 'backlight' control anywhere in the menus, then odds are the backlight is run at 100% brightness all the time. What monitor and TV do you have?
 
Hey @NoxTek, thanks for the awesome feedback.
Did you contact the ebay seller about the panel distortion? Keep us posted if you manage to get another sent to you if you have the time.

Has no one else been able to confirm the fact that U400 a has locked backlight to 100%?
 
igorz said:
Hey @NoxTek, thanks for the awesome feedback.
Did you contact the ebay seller about the panel distortion? Keep us posted if you manage to get another sent to you if you have the time.

Has no one else been able to confirm the fact that U400 a has locked backlight to 100%?
Click to expand...

I just checked and the backlight is locked at 100% for me as well. Lowering it below 100% caused it to glitch out, just as NoxTek had said.
 
igorz said:
Hey @NoxTek, thanks for the awesome feedback.
Did you contact the ebay seller about the panel distortion? Keep us posted if you manage to get another sent to you if you have the time.

Has no one else been able to confirm the fact that U400 a has locked backlight to 100%?
Click to expand...

Honestly I'm hoping the seller will take the TV back and issue a refund, not just an exchange. In my opinion this thing is bad even on a good day, at least for my tastes. I initiated a return through Ebay yesterday but sofar have not had a response from the seller.

The pixel response time on this panel is God awful. At times it literally seems like you're using an old passive color LCD screen like you would see on one of the first color laptops. It's so bad in fact that you can even notice it in 24fps movies. 60fps games and video? Forget it... it's a ghost-y smear-y mess. There is literally no point to having 4k 60hz support on a panel like this. I was so disgusted that I boxed it up last night and am back on my old Seiki SE42UGT. It may not have 4:4:4 chroma but it has good pixel response.

About the only good things I can say about it now is that it DOES indeed truly support 4:4:4 chroma at 4k/60hz.

It's also extraordinarily cheaply constructed, but I figure that's the case with all of the Ebay Korean monitors like the Wasabi Mango, Crossover, and AMH. As a small example, the plastic feet attach with self tapping screws to pre-drilled PLASTIC holes in the bottom of the TV. One of the holes completely stripped out when I was putting the feet on and I just barely had tightened it. Disappointing but I was sort of expecting it given the cost of the TV.

And yes, the backlight is 100% and non adjustable. I honestly suspect that there isn't even logic there to dim the LED backlight at all.
 
Superjoe said:
In nVidia control panel the U400 was identifying as a 289K.
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I forgot to mention in my posts above that mine was also identified in Windows 10 as a 289K. I'm guessing the firmware between the Crossover 289K is the same, or so similar that they didn't even bother to change the identifier string in the EDID info.
 
garin said:
Does anyone happen to know exactly which panel this is? It should be available as a samsung TV too right, unless there would there be some hardware difference between it and just buying the same as a TV locally.
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In the service menu (on my Zen U400) the panel is identified as an LC490EQE-PGF2, which makes absolutely no sense. That panel model number appears to be for a 49" IPS panel from LG, not a 40" Samsung PVA as the Ebay ad and literature says it has. And obviously it has a 40" panel of SOME type...

I can't tell you specifically what panel is in the Zen 400 without opening it up, but it's SUPPOSED to be a Samsung PVA panel, probably the same one used in the UHD400. In fact it would pretty much have to be since the only 40" panel Samsung produces or has ever produced seems to be the PVA LSC400FP0x models.

 
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jthom127 said:
I just checked and the backlight is locked at 100% for me as well. Lowering it below 100% caused it to glitch out, just as NoxTek had said.
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Damn (I guess?)

How about the pixel response/ghosting/smearing issue? Have you been getting that also?
 
iBurgerr said:
NoxTek:
The WM UHD400 is an RGB screen; and the U400 is a BGR. So the panels are probably different.
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You're right!

This really makes me wonder what panel is being used inside the Zen U400. The Ebay ads say it's a Samsung PVA panel, but try as I might I can't find evidence that a BGR Samsung 40" 4k PVA panel even exists. No parts houses list them, no LCD panel database list anything similar.

Anyway finally heard back from the Ebay seller StoreWithStory and they've agreed to accept a return for a refund. In fact they insisted on it, saying that ebay policy doesn't allow exchanges.
 
If the service menu doesn't give correct information and you don't want to take apart the screen then there is only one other way to identify the specific panel type.
That is taking a high magnification photo or a digital micrograph of the subpixel structure.
 
igluk said:
If the service menu doesn't give correct information and you don't want to take apart the screen then there is only one other way to identify the specific panel type.
That is taking a high magnification photo or a digital micrograph of the subpixel structure.
Click to expand...

Screenshot_20160711-042049.png


Kinda crappy zoomed in phone photo but you can definitely make out enough structure of the sub pixels to hazard a guess I would think...

What it really looks like to me is a Samsung cPVA screen as described here, only flipped upside down as to make it BGR instead of RGB... Here's a cPVA example pixel structure from the site linked above:

cpva_close1.jpg




And here is an example of Samsung S-PVA from that same page:

s-pva_close1.jpg



Who really knows though, that site may purely be referencing 1080p panels. The industry and manufacturing technologies change so rapidly...
 
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You can make out something, but it is not quite detailed enough.
It can't be cPVA, because they have been discontinued and I don't believe Samsung ever made them at bigger sizes (they stayed with S-PVA for big panels)

The current Samsung panels used in their JU/KU TV's all look like this:
http://www.hdtvtest.co.uk/image/uhdtv/Samsung-UE65KS9500/subpixel.jpg

Earlier S-PVA panels have these chevrons, and some are still being manufactured
http://www.hdtvtest.co.uk/image/uhdtv/Sony-KD75XD9405/subpixel.jpg

Pixels of the Philips 40'' BDM4065UC TPV panel are very different
http://hdtvpolska.com/zdjeciamaciek/PhilipsBDM4065UC/4.jpg

Innolux Super MVA panels often look like this, but they make some different looking ones as well
http://hdtvpolska.com/zdjeciamaciek/PFH5500/lupka.jpg
 
Thanks for the interesting post. -- I'll monitor this thread!

Just to draw to a conclusion, if not cPVA, which type could it be?
 
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