Samsung 2333SW - Image/color-relative glitching

[alecjahn]

There was a post about this before, or maybe something similar... but it sounds like it's probably the same issue.
https://www.badcaps.net/forum/showthread.php?t=20849
It ended in the request to check some voltage regulators. This is where I post my qualitative results to finish that thread. But I can't tonight... but I will continue.

The LCD freaks-out with certain images. When I acquired the display I initially thought, "Oh... hey... this one is totally fine." Then I started to adjust the color/brightness/contrast settings to my liking and noticed one of the settings caused a weird flickering glitch over the top of an open Explorer (etc) window, in a specific range of blue. This would follow that image around the scree, so it wasn't LCD-location specific, but rather signal specific.
This leads me to believe that the panel is fine, even though at the time my first thought was that the flex connectors were splitting on those columns.

I played a video on it and it started freaking out completely. Half the image would disappear, then the whole thing, then it would come back... and as expected, it would stick to its state when the image was static (video paused).

Here's a video of the problem happening.
http://www.youtube.com/watch?v=NYs6aPJ0RBI
The first clip is where the video is paused on a "bad" frame/segment. It flickers, and the "dead"/black section actually gains in brightness/contrast to some frequency, at which point it hits a breaking point (also here a lot of pixels have locked into a random color). Second clip is the same video but playing instead of paused. Third clip is a close-up of the Windows bar, where the signal-specific artifact is occurring.

I have also attached pictures of the two boards, etc.

I'm expecting this to be a "Well, some logical component is dead, you need a new board" and I'm fully prepared to make that purchase. I figured I would post about it first.

Thanks for listening.
I can do component-specific testing tomorrow after work.

[dkalweit]

Re: Samsung 2333SW - Image/color-relative glitching

I have a 2333SW with this same problem. I actually have 4 2333SW's, and this is the only one exhibiting the problem(yet?). I first noticed the problem over a year ago, but the monitor was hooked to a computer I did't use much. I recently added it to my main workstation(upgrading from 4 to 8 screens by combining my two 4 LCD workstations into one)-- and it's therefore gotten more of my attention...

This afternoon, I took it apart, expecting to find bulging caps, but I was surprised to find they all looked fine. I re-assembled it and put it back, and the problem is still there-- but I understand it more after reading this and the other post on the 2333SW. I found a specific image(with blue sky; I had used it for my wallpaper) makes it happen, but having a maximized notepad on the screen it displays fine... Another part of the same image with blue sky displays initially partially, and then has the psychadellic type of effect(it looks pretty cool, actually) until it all goes black. This monitor works fine after it's been on 10-15min, as others have reported...

I would likewise be interested in any ideas to try to solve this problem.

Thanks.

[alecjahn]

Re: Samsung 2333SW - Image/color-relative glitching

I've got a new main/logic board on order, I will let you know if that ends up repairing mine (I fully expect it will, and fully realize board replacement is less informative and less fun than component level board repair...). NOTE that there are at least two revisions of this one model - my logic board happens to be one that seems to be more difficult to find. I believe it [again, *mine*] is part number BN81-03454A, though I could not find this marking on my current board. The other board I have seen has two cable connections instead of three, and none of them are physically interchangeable/compatible. Perhaps, however, it is possible to use the other board revision with the appropriate/respective cables to connect the board to your current PSU and to the panel? Something to look into if necessary.
My logic board should be in my possession in a few days (maybe early next week at the latest).

[alecjahn]

Re: Samsung 2333SW - Image/color-relative glitching

New main/logic board arrived. No luck. I should have known it would probably be the panel... Which I will dive into (at least the board) some time.

I have found that if I lowered the brighness and contrast it would behave a little better... I could be imagining things, though. I'm going to see how long that lasts. Also, I noticed that, when watching a test movie, if I change the MagicBright mode to "sports" it would immediately freeze the screen and start the gamma ramp that ends in a white (ish) screen. A "white" screen, such as this forum will do the same on the "game" setting.
Interesting.

So again, the image is fine until it gets a signal that it doesn't like. I changed the refresh rate to 50hz through Windows (allegedly it is compatible, but I could be totally wrong) and only got a flash and then a blackish screen.


Either that, or I ordered a board that was also bad. Which is certainly possible. But it wasn't expensive so I won't be out much if this one goes to the back of storage with a couple more that haven't been resurrected.

[alecjahn]

Re: Samsung 2333SW - Image/color-relative glitching

Additionally, the panel board has a small trimpot on it. I measured it from all angles, and then commenced tweaking it with the monitor on. I'm sure someone could tell me what it is for, but anyway it had no effect on the problem (but did alter the brightness/contrast/gamma/something of the picture a fair bit. I didn't play with it for too long and set it back to where it was.