Samsung Syncmaster 225BW

[shodanx]

Re: Samsung Syncmaster 225BW

This 13 years old thread is amazing, it should go in an internet museum.

So I have 5 display setup that consists of one 40" monitor surrounded by 4, ethernet wired samsung 225bw

Picture of my full setup (from last year or so)



Now I had a problem with these display, sometimes they momentarily turn black and come back (and the backlight stays on during this !)

Sometimes the front panel freezes and I have to flip the switch behind to reset it. Sometimes the screen will become 100% red only because the color values have become wrong (press second button from the left 4 times to fix this, if it's not frozen, that will reset all the colour settings by setting the display values to "game" colours)


So I noticed this was become more of a problem with heat so I went and dismantled 3 of them, fixed the busted backlight inverter caps. Also changed some that were not busted. In all cases that did not fix it.

Here I am fixing the caps



So I had the electronics powering the boards out of the case like this and pumping the kind of dynamic colourful scenes that have high change of triggering the black screens.


Lo and behold, I cannot get it to do black screens or even freeze while out of the case !?

I took a measurement of the chip in the middle, 43C in open air

Here is the board close up



Couldn't find anything explicitly bad with it.

So I decided maybe it is the heat that is doing it ?

Then I took my big hairdryer and shot it at the PCB on full blast.

And that triggers the problem in seconds.

When it cools down it doesn't do it.

So I decided to cut a window in the case



Here is the finished product for now, until I can install a fan




I asked for driving my mini fan at low speed so it doesn't make noise

on reddit, but haven't got an answer yet

https://old.reddit.com/r/AskElectron...s_12v/idrmzi9/

I made this video of trying to power this fan with a programmable power supply

If you notice the samsung 225bw has for some unknown reason a 12V barrel jack output ! And I'd like to use that to power the fan at low speed.

[Per Hansson]

Re: Samsung Syncmaster 225BW

I would check the ESR of those surface mount electrolytic capacitors.
Probably after all these years with heat they are bad.