Digitalfiend
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U2414H, Bought two but I have a problem: horrible dithering with whites/greys on one of them

I bought two U2414H last week (separate orders) and upon receiving the first one, I immediately noticed something off about it. The monitor seems to "clip" when attempting to display light grey/near white values, leading to a lot of dithering. I calibrated the monitor with my xrite device and noticed that no matter what I did, I couldn't get it to match my older Dell U2214 (the 2nd U2414H hadn't arrived at the time.). I can also see tiny faint horizontal lines across the monitor, but assumed it was the larger pixel pitch so figured I'd wait until the other U2414H arrived before worrying too much. The 2nd U2414H I received calibrated without issue and looks *beautiful*. No faint horizontal lines and absolutely no dithering that I can see. I'm using the latest NVIDIA driver for my GTX 580 and have both DVI outputs set to use the full range of RGB values (0-255); this is now available as a desktop video configuration option in the NVIDIA control panel. I'm using a DVI-to-HDMI cable. I tried switching the cables around thinking perhaps one of the ports was off somehow, but the results were the same - the first monitor seems to be defective somehow. I even bought new cables thinking there might be something wrong. I tried resetting the "bad" monitor but that didn't do anything; I also compared the sRGB calibrations between the two monitors and they are drastically different.

It's a bit hard to tell from the picture below but this is an example of what I'm talking about.  The blown out sun in the cloudy sky is VERY smooth on the "good" U2414H (left) and blocky on the "defective" one (right).  Note: the colours are not off like they seem in this picture (just the angle of the monitor and the iPhone.)

Unfortunately, this monitor is practically useless for its intended purpose. I also don't understand the fine horizontal banding either. The monitor on the left doesn't exhibit any banding - I can see the pixels if I look very closely but from a working position, they are practically invisible. The right monitor on the other hand appears soft and I can clearly see the horizontal banding from a working position in my chair. It's quite ridiculous actually.

So unless anyone has any suggestions, I think I'm going to have to call Dell and get this defective monitor exchanged for a new one as it is well within 30 days. The U2414H that is working properly is absolutely fantastic: great clarity, saturation, and color reproduction. Nice size too. I just need two of them working properly!

Summary of what I've tried:

- new cables
- switching DVI ports
- ensuring NVIDIA card is outputting RGB 0-255 instead of 16-235
- calibrated using XRite device
- tried resetting monitor
- tried using factory sRGB calibration
- manually adjusted brightness/contrast and RGB values

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Digitalfiend
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RE: Bought two U2414H but I have a problem: horrible dithering with whites/greys on one of them

Just did a bit more testing:

The good monitor is Rev A03 (Dec 2014) while the faulty monitor is Rev A01 (Oct 2014).  I wonder if this is the reason for my issues.  It seems strange but it's almost as if the AG coating is different on the A01 - maybe there is a slight difference in the actual LG panels too between A01 and A03.  Who knows.

I tried changing the RGB values and lowering them quite a bit helped reduce the chunky gradients in ultra light greys/near-whites.  The horizontal lines are still quite noticeable compared to the A03 panel though and I still can't quite get the colours to match.

 

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Digitalfiend
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RE: Bought two U2414H but I have a problem: horrible dithering with whites/greys on one of them

Spoke with Dell technical support and the tech had me go through the LCD test.  The grey background portion of the test showed very visible (at least to me) horizontal banding - best way to describe it is like seeing tiny gaps between the physical pixels of the panel leading to grey-dark-grey-dark-etc pattern horizontally (but not vertically); I suspect this is what yields a softer image and a very fine mesh-effect when viewing under normal use (desktop display, pictures, etc.)  I tried the same test on the good A03 panel and didn't see this effect.  If I look really closely at the A03 panel I can see the normal physical pixel grid but the A01 exhibits faint horizontal lines from a distance and even looks slightly soft (not to mention the colour issues.)   

I even tried comparing the sRGB factory calibration between the two monitors and the difference is significant.  The A01 panel under sRGB mode has a reddish-cast to it whereas the A03 panel is almost indistinguishable from my custom calibration and what I'd consider "spot-on".  I really feel there is something wrong with my first monitor; the Dell technician agreed and is sending a replacement.

I know Dell gets bashed a lot for their overseas call centre support (and I'm sure some of it is deserved) but other than the long wait times, including frequent "can you hold for 3-5 mins?", both the customer service rep and technician that I spoke with were helpful and addressed my concerns without making me feel like they were robotically reading a script.  Overall I'm satisfied with Dell support.  It took about an hour to get everything setup for the exchange.

I asked the tech if he could make a note in the service request to instruct the warehouse dispatcher to ship out an A03 panel, just in-case there is something off with these A01 panels.  It's a long shot and I'm probably going to end up with another A01, but figured I'd mention it to the tech just in case.

 

Digitalfiend
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RE: Bought two U2414H but I have a problem: horrible dithering with whites/greys on one of them

I received the replacement monitor, which is a refurbished unit, even though my defective monitor is only two weeks old.  I called Dell and they are sending out a new unit this time (hopefully!)

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Moderator
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RE: U2414H, Bought two but I have a problem: horrible dithering with whites/greys on one of them

All new and refurbished should be at A03 which is the latest revision. You should check the refurbished for the firmware version. If A03, test it before sending it back.

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Digitalfiend
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RE: U2414H, Bought two but I have a problem: horrible dithering with whites/greys on one of them

Hey Chris, you are correct.  The refurbished unit is A03, though you can see the original A01 label peeking out from underneath.  The monitor shows that it was made in May 2014.  I didn't want to take it out because I'm not accepting the refurbished unit, but I guess it doesn't matter if I do because the unit isn't taped up/sealed or anything.

Going to try it now.

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Digitalfiend
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RE: U2414H, Bought two but I have a problem: horrible dithering with whites/greys on one of them

Plugged in the refurbished A03 monitor and it matches the good A03 that I have perfectly.  Factory sRGB modes are a match (to my eyes) and there is no odd dithering and no faint horizontal lines.  For me this confirms that there is definitely something wrong with the A01 panel that I've got. 

I'd actually have considered keeping the refurbished A03 panel, but the bezel looks worn and I have a tough time accepting refurbished units to replace brand new products.  I will have to wait for Dell to send out the new replacement monitor and hopefully it is an A03 too.

Chris, do you know if I just send back the refurbished unit using the included waybill - I assume it doesn't matter that Dell is expecting the original monitor & serial #, since that will be going back too once the new replacement arrives.  I just don't want to get stuck footing the bill for this refurbished unit.

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Moderator
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RE: U2414H, Bought two but I have a problem: horrible dithering with whites/greys on one of them

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Digitalfiend
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RE: U2414H, Bought two but I have a problem: horrible dithering with whites/greys on one of them

Great to know, thank you.

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