Is My Monitor Possessed? Strange Display Issues After Standby

[AKG]

I don't know if this is the right forum for this; please move it if it belongs elsewhere.

I have a very strange problem with my monitor. After the computer has been left for a while (and I think sometimes if it is put on standby) and then we come back to the computer to use it, the screen starts to do something very weird. First, the desktop appears and dissappears repeatedly, but when it appears, it doesn't just flash on the screen, it starts out as a vertical line in the middle of the screen, then stretches horizontally til it fills the screen, then flashes off (then it starts back as the vertical line). It does this 7-8 times, then either it collapses to a vertical line, and then the display goes out altogether (black screen), or the screen starts to shake. If it starts to shake, the shakes gradually slow down and it goes back to normal. The shaking is sort of like how the computer looks when you degauss it, but it's not exactly the same. It's an old monitor that my mom's work was giving away and we took it. The computer itself is fine I think. Why would something like this happen? Thanks.

 

[dduardo]

Um, its an old monitor. What do you expect?

 

[Ivan Seeking]

In the most general terms capacitors are the usually most likely component to fail. If you know how to work safely with monitors, ie the high voltage [15 - 30KV] which can be lethal, and if you can test capacitors, it is often possible to check the large capacitors and to find the problem in fairly short order.

The old TV repair guys would actually troubleshoot, with the circuits powered, by placing a test capacitor in parallel with each existing large capacitor in the HV circuits; one at a time and by hand! I have watched them do it but I sure wouldn't try that approach. I have found bad caps and fixed the problem in my own sets a couple of times...actually, I think several times. Once I even fixed a volume problem this way. Just look for the most likely circuits and start testing.

 

[Ivan Seeking]

I kept saying large caps; in the case of monitors this includes the disk caps. Tantalum caps and such are not usually the problem, in my experience. Disk caps and standard, +-20% electrolytic caps are always suspect.

 

[Oyéah]

I bought some neodymium magnets. When they arrived I opened them in front of my computer. The monitor immediately went haywire, so I read the instructions that came inside the package I just opened, and took the magnets far from my computer. There are some items that can make a monitor do strange things. Maybe you are just underpowered, and other items on your circuits make it difficult for your monitor to get its fair share of power back, once it goes down.

 

[Didd]

Is the power system of the computer the same as the power system of your house.
In other way, is the power of your house agree with that of you computer.

 

[Oyéah]

If you have a power strip, or two that you run your equipment from, then you can underpower your system, and things vie for the power they need. Old monitors use more energy. Since you need surge protection for your computer system, most people just take one big power strip and plug everything into it from one outlet. My house power is various, in that some of it is updated, and some is not. Some plugs are better than others too. I have power strips where one outlet is bad. I need an electrician, but that is not happening, anytime soon. Try plugging your monitor into another outlet on another circuit, to see if it improves.

 

[Anttech]

hardware problem... old monitor, to quote above what do you expect... the "tube" has probably gone... You could try and fix it like Ivan Seeking is saying or just fork out and buy a new TFT monitor :-D

 

[chroot]

LOL you people come up with some wacky suggestions. It sound to me like one of the yoke control boards has failed.

- Warren