Monitor buzz

[Hokiefyd]

I have an ASUS VH236 monitor that I've had for a number of years now...probably since 2010 or 2011 (bought new). It has developed a buzzing sound at the top of the monitor -- you can clearly hear it through the air vent in the back, and you can hear it enough to be bothersome from the front of the monitor. Though this monitor has built-in speakers, I don't believe this has to do with the speakers. The pitch and volume of the buzz changes with the "visual load" on the screen -- lots of deeper/darker colors tend to make the buzz louder -- and I can change the buzz by moving those colors on and off the screen (scrolling on a website for example).

Is this just how the power drivers, or whatever they are, fail in a computer monitor like this? It's becoming so bothersome, I'm considering replacing the monitor...but that's a cost I'd rather not absorb, so I'd to try to fix it if I can. Changing the brightness of the monitor, as suggested on some websites, does not change the sound, unfortunately.

I appreciate any suggestions.

 

[Leo99]

I'd get a can of compressed air and blow out as much dust as I could and remove and retighten all the connectors. Other than that, I don't know what else you could do besides give it a good whack with your hand.

 

[SwampSurvivor]

Capacitor whine I bet.

 

[camrydriver111]

Sounds like transformer noise. I don't think you can do anything about that.

 

[Klutch9]

We have a fluorescent LCD monitor at our office that does the exact same thing. Could it be a ballast for the fluorescent bulb(s)? Either way, probably not fixable the way these things are designed.

 

[JHZR2]

High frequency switching components or capacitors would be my guess.

 

[Falken]

I have that at work on an Acer Monitor.

I find if you turn down the Brightness from stock levels (way too bright) it consumes less current and the issue goes away.

When it is at stock Brightness, if I open a white excel sheet it makes the buzz like it is over driving the led boards.

Hope that helps.

 

[Johnny2Bad]

The monitor is failing. I don't mean to start a panic, as they can run a long time before they quit, but it's the switching supply, possibly capacitors in the switching supply but whatever. These two circuits drive the monitor itself.

The noise varies depending on what the display is asked to do because some colors on an LCD use no power (transparent to the backlight) and others use up to maximum power (opaque to the backlight).

Do not try to service this yourself. Fatal voltages present and said voltages and currents remain stored in the monitor for a long time, months even, after last power-down.

You could have it serviced, but these can be expensive parts, so consider just upgrading the monitor when you have some extra coin, and be sure to recycle the old one. And it's worth repeating, although it is failing, it may run for a very long time before disaster strikes, so if you can put up with the sound, run her as is.

 

[sleddriver]

That buzzing you hear could be arching. It'll happen if it gets too dusty inside. If you're handy, unplug and pull the back off and look for signs of arching around the perimeter of the backlight. Once arching begins, it blows out a piece of metal, increasing the gap each time. This can lead to the HV supply failing over time.

 

[asand1]

Sounds like bad filter capacitors allowing AC ripple, and causing coil whine. Google monitor power supply recapping. Check out badcaps.net also. Easily DIY, and I would recommend doing this project if you are at all handy. Watch out for !!HIGH VOLTAGE!! wear rubber gloves and use a screwdriver to discharge any caps before handling them.

If you would rather replace it, you can send the old one to me;-)

 

[Lubener]

Originally Posted By: camrydriver111
Sounds like transformer noise. I don't think you can do anything about that.


Laminations on a transformer.Try tapping on the cabinet and the pitch may change.

 

[Lubener]

Originally Posted By: asand1
Sounds like bad filter capacitors allowing AC ripple, and causing coil whine. Google monitor power supply recapping. Check out badcaps.net also. Easily DIY, and I would recommend doing this project if you are at all handy. Watch out for !!HIGH VOLTAGE!! wear rubber gloves and use a screwdriver to discharge any caps before handling them.

If you would rather replace it, you can send the old one to me;-)


Ripple usually will be seen in the pix(hum bars, weave, low power levels from open caps may cause a high pitched squeel or even power up). Without a schematic, your shooting in the dark as caps used in power circuits are scattered across the pc board. An inexperienced "tech" will change everything in sight and may get lucky.If you go inside, watch out for the "biggest" capacitor, the CRT if it is one. There could be 20+ kv stored under that suction cup which is stuck onto the crt( if your moitor is a crt, not familiar with your model.If it's an LCD,it may be the external power supply if it has one.