My LCD monitor display is going black (turning off). It's a Samsung SYncMaster 2233 widescreen.

I am trying to figure out if there is anything I can do about it, or if the monitor is junk.

I have tried multiple computers, all have the same issue. I have tried a different vga cable, same issue. Power and video cables are tight / double checked.

When I power on the monitor, the blue light turns on at the bottom. Then a second or two later the video comes up as expected and it looks fine.

However, about 2-3 seconds after that, the screen goes black. The blue light is still on and solid at the bottom (blue light normally flashes when the monitor is sleeping).

If I power cycle the monitor, same thing happens.

With no computer connected or when I unplug the vga cable, I see the searching for signal message "digital", then the screen goes black. However it usually shows "digital" then "analog" after that and switches between the two a few times.

The buttons on the side do not do anything, although they may be, I just can not see if they are or not. I can usually get the "digital" message by pressing the buttons on the side, but then it quickly goes black again.

What is really strange is sometimes I can get it to work fine. I am not sure what the difference is. Last week I connected it up and it worked fine and it stayed fine for at least a week! I did not turn it off or anything, I just let the OS put the display to sleep. Then this week one morning I started having the screen going black issue again.

Seems like something is either loose inside or beginning to fail.

Do you think there is any hope for it?

update: pushing the input select button causes the "digital" and "analog" messages to flash on the screen, but only for a few seconds then it goes black. When it was working properly, those messages would flash back and fourth for probably 10-20 seconds then a message would show saying check input signal, but now just a black screen.

  • Is it possible to select the video input on your own? If it is, you should try it, if not, then something seems to be wrong with the input selection, in this case you should contact you hardware supplier.
    – Michael K
    Jul 21, 2011 at 12:04

2 Answers 2


My monitor does the exact same thing, and I did some research a while back and I found that the inverter was broken (which was kind of logical too, 'cause back then, a lot of electrical equipment started to fail due to a bad batch of capacitors ), but I can't find that page again.

  • Inverter !! was the part that turns one current to another.
    – Raz
    Jul 20, 2012 at 7:46
  • Edited in the fact that its an inverter (converts DC to high voltage AC in this case), and the reference to the dread capasitor plague. I note that on stack exchange you can edit your answers at any time. I'd add that it may also simply be bad caps on the power part of the monitor, and replacing all surface mount caps may help. I have a 'project' monitor where i replace caps as they fail to work out which caps my 2 identical dead monitors need to be replaced ;p.
    – Journeyman Geek
    Jul 20, 2012 at 8:47

Check for contamination in the DVI and VGA connectors on the monitor, it's possible that the automatic source detection is preferring the port which isn't connected due to some contamination fooling the monitor into seeing a connection. Use a can of air-duster to clear contamination.

Also, check that the monitor is actually shutdown when it appears failed - when the monitor goes black, does the screen appear the same as when the monitor is powered down? Shine a bright light into the monitor and check whether there is actually an image displayed. It's possible that the backlight is failing.

  • I think you are on the right track with the backlight!! In fact when I turn it on you can tell the back light is on - it's not quite as black. You can see it go off. Yes, if I shine a light right where the 'analog' 'digital' message is, I SEE IT!! So it's the back light. So is there anything I can do about that? The back light comes on every time I power it up, it just shuts down quickly. Jul 21, 2011 at 14:42
  • If you have a local electronics wizard handy, you could see if they can take a look. Otherwise if you're not still covered by warranty, your best bet is to replace the monitor.
    – Mike Insch
    Jul 21, 2011 at 15:09
  • 1
    Just FYI, soon after I asked this, I gave the monitor to a co-worked, who has been using it for almost a year now with no problem! So this issue appears to be related to MY computer somehow. His machine has had no issues. May 8, 2013 at 19:19

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