Humming/Whining from monitors external PSU, help!

[Vizuka]

Hi, so I just got my new LG 34UC98 Ultra-Wide monitor, it seems to work great except for a few things. The main thing being, the external power supply of the monitor seems to be making a humming noise while the monitor is on, not dependant on what I am doing on the monitor. And when the monitor goes into 'Stand-By' mode, the hum changed to a high pitches whine. Is this normal? The whine is not very loud but it is definetly audible in a very quite room. As for the humming, it is the same deal here, it is not very loud, but audible in a quiet room for sure.

Even when the monitor is completely Off, a slight whine can be heard. So I am just wondering, should I be worried about this?

All answers are appreciated!

 

[greens]

The term for this is Coil Whine.
It is a sign of a... less than perfect... power supply.

It is somewhat unavoidable unfortunately. A high quality after market PSU will probably NOT exhibit this noise.

I have 3 identical monitors and their power bricks all make unique noises... very annoying.

 

[Vizuka]

The term for this is Coil Whine.
It is a sign of a... less than perfect... power supply.

It is somewhat unavoidable unfortunately. A high quality after market PSU will probably NOT exhibit this noise.

I have 3 identical monitors and their power bricks all make unique noises... very annoying.

What monitors are those? And is it even unavoidable on a monitor like the LG 34UC98? I mean, it does cost around $1000 :/

 

[greens]

Yeah i mean, it is unavoidable so far as it is a byproduct of "switching power supplies" which most modern ones are. You can look up why at your leisure.

Even a good monitor is going to have the cheapest parts from the lowest bidder... Ever see glue inside electric devices? The reason it may be there is preventing a coil from vibrating. But that takes time and money to add to every PSU...

Like i said, if its an external brick you can replace it with a high quality one.

If it is internal... is it new? Sometimes these things have a break in period and the sounds and smells go away.

 

[nukemaster]

Less than perfect makes it sound bad. Even among the same batch of parts some will vibrate while others will not. Just the slightest variation in switching frequency from one unit to the next can cause or change it.

This is not to say that some are not slightly better(and encapsulated to reduce the issue. My old notebook power supply was poured[liquid that hardened after], no noise got out of that thing.). A faster switching power supply may also have less noise since it may get out of our hearing range.

It sucks that it happens, but in general it will not cause any harm. I have a monitor that has a power supply that has had coil whine for almost 8 years without issue. At lease your external power supply may be able to be placed in a location that it is less noticeable.

While linear power supplies do not have this kind of noise, they are also so inefficient that most users are best to stay away from them for things that do require them to work well(Audio and lower powered devices tend to use these, but even those are moving to switching.).