NEC LCD 1760NX feedback/help requested

[Rodéric]

Bought one, intended to review it for www.paraknowya.com but the monitor exhibits horizontal waves...

At first you don't notice it, but after a while you get tired and have a headhach, and find that the problem is indeed those 'waves", which are more easily seen on dark colors (windows dark gray).
Call NEC, get a replacement screen, which arrived 2 hours ago...

And it has the same problem...

Anyone with such a screen having this problem, heard about it ... ?

Checked on my RadeOn 8500 in DVI and DSub, recommended settings, and also a Rage3D board with the same problem.
My iiyama 17" LCD screen on the other hand don't show anything like it, neither in DVI or DSub...
I'm not the only personn to see the effect so it's not me
:?

 

[Captain Chickenpants]

Hi,
These waves, are they vertical lines going across the screen?
Is it an analog monitor?
If so then it is likely to be the sampling of the input signal is slightly skewed, most analog LCD monitors will have some controls which should allow you to adjust this, normally called something like phase and offset.
If it hasn't got this then (if you are feeling brave) you could download powerbar or any other program that lets you fiddle with display timings, and try tweaking the horizontal timings, by adding or subtracting a pixel to either the front porch or back porch (I don't think the sync length will have much of an affect).

CC

 

[Rodéric]

Vertical lines going from up to down or down to up depending on screen refresh rate.
Noticable when brightness around 50% and contrast around 25% or lower (my iiyama is set much lower and don't exhibit anything like that).

When in DVI-D mode (using DVI cable) it's far less noticeable than in DSUB/Analog mode.

There's no settings in DVI mode, they are available only in Analog mode, but tweaking them doesn't solve the issue.
Since the issue exist both in DVI and Analog mode [and not on my iiyama screen], I suppose it comes from some common electronic part.

 

[RussSchultz]

Sounds like you might be having some power supply issues. Are you on clean power?

 

[Mariner]

I've used an 1760NX at home for about a month and can't say I've noticed any such problems. I'm using the Analogue connection at the moment.

One thing I would say is that the display seems to be a bit 'grainy' compared to my old monitor (Eizo L365). Hard to explain exactly, but some photos don't display that well. I'm not sure if this is to do with the screen itself as the specs quoted by NEC say it can display 24-bit colour, but other sources I've read indicate that the particular panel used in this display is limited to 18-bit.

As the computer is on my home PC, I rarely use it for much more than an hour or so at a time.

 

[Rodéric]

Sounds like you might be having some power supply issues. Are you on clean power?

I've tested it with a 'onduler' (the thing you put your PC on to protect it from power shortage and all), and without, in both cases it exhibits the problem.

I've connected it to another power connector (in another room) and it still exhibits the problem...

Mariner:
I think I get what you mean by 'grainy', I've an LCD iiyama just next to this screen (yeah also put them both far away just in case), and it feels less 'grainy".
Could you do a quick test for me ?
After about one hour of use, set your desktop color to 92,92,92, remove any wallpaper and look at the screen (you'll need a large empty area preferably), and tell me if you don't see horizontal waves...
You notice them more easily by reading your icon text.

If you don't see anything, can you gimme your screen serial Number, and tell me about your graphic card and video settings, please ?

 

[RussSchultz]

Do you have all items connected to the same ground? (No antenna, cable tv connection, etc to the computer?)

I got similar problem on my projector when hooking my cable box up to an amplifier (which was on a different ground).

 

[Mariner]

Ingenu,

Well, I've tried what you asked and have almost gone cross-eyed in the process! 'Graininess' aside, the picture is rock solid with no visible defects waves or otherwise.

As I mentioned, I'm using the analogue connection. The graphics card is a cheap Inno3D GeForce3 Ti200 (Digital Vibrance off). Using the Naviset tab in the display settings, I have brightness at 100% and contrast at 50%. Refresh rate at 60hz, obviously. Native resolution 1280x1024 at 32-bit colour.

I think the 'grainy' problem is due to colour banding, to be honest as I can see banding in something as simple as the title bar of windows. It's not been too much of a problem for me as I've only used the computer for web browsing since I got this monitor. I'm due to upgrade my computer soon with new graphics card etc. and I plan to do more stuff with graphics then. I'll have to see then if I notice the banding more once I dust off my copy of Bryce!

Serial number for this screen is 31150168GB, by the way - the groovy black version of the monitor. 8)

 

[Rodéric]

Do you have all items connected to the same ground? (No antenna, cable tv connection, etc to the computer?)

I got similar problem on my projector when hooking my cable box up to an amplifier (which was on a different ground).

mmh...
Cable Modem... DVI & VGA out, SBLive! out to Altec Lansing ACS33, SBLive! in to mircophone, nothing else.

Thanks Mariner, I've asked you your S/N to see if it can be a whole set of screens which are affected or only one.
The effect is even noticeable on win2k std blue background although less.

Can you try the test on my above post with brigthness to 50% and contrast to 25% (or less) ?

 

[Mariner]

I've tried the test at 50% brightness/25% contrast (very dim image!) and still haven't seen any problems with 'waves'.

I'm using WinXP Pro, by the way.

Off to bed now (early night required!).

 

[Rodéric]

Thank you again

I'll contact NEC again to know more about the problem.

 

[Rodéric]

They fail to reproduce the problem on another screen, so either I got two faulty screens, or there's something wrong somewhere....

Tried with many PC and video boards and always get the wave/flashs that is noticeable on large dark areas.

Do anyone know people with NEC MultiSync LCD 1760NX, living in a 220V/50Hz country preferably ?
(could be a problem with power line sync, that wouldn't be seen on 60Hz but would in 50Hz)

I'm really annoyed by this problem, I bought NEC because I thought I won't have any problem... better have bought IIYAMA again.

 

[Rodéric]

UPDATE:

NEC 1701, 1760NX, 1760V share the same panel, and all exhibits
"but they clog a bit in dark tones"- Tom's Hardware.

 

[Johnny Rotten]

Philips/Lg have just released their new 16ms 17" flat panel. If you want to try out a different panel manufacturer you may want to give them a look (they're also the #1 or #2 flat panel manufacturer in the world - Samsung is the other - so their quality should be fairly good).