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EDIT: Originally posted on StackOverflow but removed due to off-topic. One suggestion was that the backlight needs replacement. I am yet to try that solution.

I have recorded the issue in this video

I would include system specs but the fact that this happens to the monitor even when it is detached from any of the computers I have tried it on makes me suspect that the issue is with the monitor itself rather than with any of the systems.

Screen model: Samsung 206BW
Screen type: GH20WS

I received this screen from my colleague who would've otherwise thrown it away and it worked ok in the beginning but then the above issue started happening. The screen is turned on but is completely black and once every 3-4 seconds it flashes really quickly and then goes black again. This happens regardless of the screen being connected to a computer or not. When this started happening I would just wait it out as it would turn on after about 5 minutes. When this didn't work I started switching between 2 monitor display (extended screen) and duplicate screen and it would eventually work out (I hardly think that this is the reason it worked as it probably would've worked if I waited long enough but superstition).

I was told that it could be the monitor cable that is either damaged or loose but the video above where I filmed the issue is when the only thing that is connected to anything is the monitor to the power outlet which removes that possibility as well.

I've been wildly guessing on other likely issues but since I'm no expert in this I ask you; do you have any suggestion as to what the issue might be and what I could do to resolve it?

EDIT2: This is the inside of the circuit board. It looks like the capacitor on the upper left on the first picture is broken and I will try to replace that. Are there perhaps any other parts that seems broken as well?

share|improve this question
I once had a Laptop with a broken backlight, if you held it in a special angle you could still see the content on the screen. Not clear enough to read it, but clear enough to see all that was missing was light from the back. So maybe you can use that approach to verify your hypothesis. With your Nick, you could of course always give it a good De-Gaussing. Just kidding :-) – TheUser1024 Mar 9 '14 at 9:28
You funny you :) I had that issue on another laptop but for this external screen I can't see anything, or I just have bad eyes :) – MagneTism Mar 12 '14 at 16:05
up vote 1 down vote accepted

One possible reason is that the electrolyte capacitors used in monitor's power supply have dried / otherwise broken, and they do not work as required. This is a common problem with many electronic devices nowadays, and one of my own monitors suffered from this problem. After I replaced the capacitors, it works perfectly. has some more information on the problem.

In order to fix the problem, you have to open the monitor from its case, detach the power supply, and then use soldering tools to remove bad capacitors and put new ones in place.

share|improve this answer
I will start with trying this, might take some time before I can get back to you if this worked or not since I only have soldering equipment at work. Thank you though, I will reply again once I tried this. – MagneTism Mar 12 '14 at 16:06
The obligatory words of caution here: Be sure you know what you are doing. I suppose there are no equally high voltages in LCDs as there are in CRTs nevertheless, be safe please, there is a group of horses (aka KillerWatts) waiting in the socket to kick you hard. ;-) – TheUser1024 Mar 12 '14 at 16:24
Yeah, be sure to disconnect the monitor from mains before soldering anything. – Tero Kilkanen Mar 12 '14 at 17:54
I have an update! This is what the inside of the circuit board looks like. I have only soldered simpler things, so I can't really tell what is broken and what is not, but one of the capacitors (seen on the first, fourth and fifth picture) has a hole in it which I guess is one of the issues. Can you see if any of the other parts are visibly broken? – MagneTism Mar 16 '14 at 17:33
The capacitors are definitely broken. At least the three capacitor group next to the wires to the panel should be replaced. I would replace all of them just to be sure. – Tero Kilkanen Mar 16 '14 at 19:06

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