Question Laptop fan buzzing but only when in a warm room.

[yakeub]

Hello.
The fan in my laptop makes a buzzing sound, but only when the laptop is used in a warm location, as in when the outside temperature is high.
Here are some scenarios to include the "research" into the problem that I've done to better present the problem.

1. I'm using laptop for gaming/software/video streaming, using a lot of resources. The temperatures inside of the laptop are high (though no overheating, no throttling), the fans are spinning and I can hear them working. But I'm in a room with an open window, and the temperature inside of the room is rather low. Not cold, just not hot either. And there's no buzzing in that situation.

2. Another time, I'm in a small room, which is actually warm. But I'm only using the laptop for browsing the internet, using very little resources. The temperatures inside the laptop are low. Suddenly, the CPU fan starts buzzing. Shutting down the browser stops the buzzing after a few seconds.

Whenever the outside temperature is warm, the fan eventually starts buzzing. If the room is not warm (again, not cold, just not particularly warm), no buzzing whatsoever.

I've checked the fans, they're all definitely clean. I'm also using a cooling pad, and the temperatures inside of the laptop rarely get anywhere close to the high end of the spectrum, usually are close to the minimum.

I've monitored the temperatures thoroughly, believe me. The buzzing only occurs, when the temperatures OUTSIDE of the laptop are high.

So my question is, assuming that it's the fan that is buzzing, why would it do it in this particular situation only? It's a bit beyond me, but could it be a problem with some internal sensor that reads off wrong temperatures and makes the fan spin too fast when it doesn't need to? Is there any way to turn the fan down a bit without risking any permanent damage? Unfortunately my BIOS doesn't offer any way to control the fans, so that option is off. Like I said, with the cooling pad and the fan in standard mode the temperatures are great, so maybe there's some flexibility?

Thank you all in advance for any suggestions.

 

[Ralston18]

Could be either outside temperatures or internal temperatures. Or a combination of the two.

Heat causes expansion and if there is some part of the laptop expanding due to being loose or just designed to tight specifications then the fan blades may move with that expansion and come in contact with the case.

Or perhaps when the fan is spinning and likely moving a bit just as an opposite reaction to the air being pushed. Depending on case and fan designs the movement could be straight or twisting.

The buzz could also be resonance based on the fan(s) speeds in certain combinations.

When the buzzing occurs try putting a finger on various places around the outside of the laptop's case.

Determine if the buzz stops directly or with just a small amount of pressure.

There are all sorts of forces involved and about the only way to get a sense of things is to open the laptop and inspect. Generally not recommended for anyone not accustomed to doing such things.

 

[yakeub]

Thank you for your answer!
There's been a development. I've tried to apply pressure as you said, and I noticed that the buzzing doesn't seem to be coming exactly from the CPU fan. After "examination", I've determined that the buzzing is the loudest in the bottom left corner of the laptop, as opposed to the upper left corner where I believed it to be.

I've circled the area where the buzzing seems to be coming from: https://ibb.co/BshNgxB
On the bottom of the laptop in that area there seems to be some "opening", "vent".
That's where the buzzing is by far the loudest.

What is that component? Could it be causing the buzzing, or is it just because of the vent that this is where it's the loudest?

 

[Ralston18]

Go online and look for some links showing/presenting disassembly of your laptop.

I am not suggesting or even hinting that you take your laptop apart.

Use the links to get a sense of the internal components and the overall layout.

View: https://www.youtube.com/watch?v=Hhqm2yg_aiI


http://www.laptopultra.com/guide/acer-aspire-v17-nitro-vn7-792g-disassembly/

I believe that the area you circled is a speaker.

Play some music and listen in that area. If you up the bass does the buzzing get louder/stronger?

 

[yakeub]

Go online and look for some links showing/presenting disassembly of your laptop.

I am not suggesting or even hinting that you take your laptop apart.

Use the links to get a sense of the internal components and the overall layout.

View: https://www.youtube.com/watch?v=Hhqm2yg_aiI


http://www.laptopultra.com/guide/acer-aspire-v17-nitro-vn7-792g-disassembly/

I believe that the area you circled is a speaker.

Play some music and listen in that area. If you up the bass does the buzzing get louder/stronger?

Yes, it's a speaker, thank you.

The speaker doesn't seem to buzz because of the audio, I've tried it in various settings including ridiculous bass. Plus, I rarely ever use the speakers, I'm mostly using the headphones, and the buzz can occur when there's no audio playing whatsoever.

Could it be that the fan is somehow making the speaker vibrate and buzz?

But still, would that explain the second, crackling noise?

 

[Ralston18]

Perhaps a combination: vibrations/buzz/resonance if the speaker is loose.

And that could have created a bad connection with the audio wires and thus the crackle.

Because you do not use the speakers per se, I would lean towards the speaker in question being loose and vibrating with the fans or maybe internal airflows. When things warm up and expand the speaker probably has more freedom to move.

Do you feel any airflow in or out of the speaker "vent"? By blocking any airflow are you able to stop the buzzing to some extent or another?

 

[yakeub]

Perhaps a combination: vibrations/buzz/resonance if the speaker is loose.

And that could have created a bad connection with the audio wires and thus the crackle.

Because you do not use the speakers per se, I would lean towards the speaker in question being loose and vibrating with the fans or maybe internal airflows. When things warm up and expand the speaker probably has more freedom to move.

Do you feel any airflow in or out of the speaker "vent"? By blocking any airflow are you able to stop the buzzing to some extent or another?

I don't feel any airflow, but yes, covering the "vent" makes the buzzing slightly less hearable. I wouldn't say it's actually quieter at its source, just less hearable when the vent is covered, either by hand or when the laptop is lying flat on the table. Applying pressure does nothing, sadly.

So I suppose it can't be helped without opening up the laptop?

Although to be honest, the buzzing itself isn't unbearable, it's just that it's the vanguard of the crackling, which needs to go. So if the crackling is caused by the wires, would disabling/uninstalling the speaker perhaps help to stop the crackling?

 

[Ralston18]

Look in Device Manager. What audio devices are listed?

You may be able to disable the onboard speakers in some manner.

Control Panel and BIOS may provide other means.

I tend to associate crackling more with a "spark" (as in a static electricity). A charge builds up in the computer and eventually jumps through the speaker wires and the speakers respond.

Here is starter link:

View: https://www.youtube.com/watch?v=ipQ1e7wREtQ


Watch and then google for similar links. Try to find additional options and some consensus with respect to an option that seems viable for your laptop.

Make discreet changes and keep notes about what changes were made and where you made them.

Just in case a roll back is needed.

Overall, try as much as possible. Opening the laptop being a very last resort. Hopefully avoidable.

And someone else may join in with other ideas and suggestions. I have no problem with that.

 

[yakeub]

Thank you very much for your help, I'll try various things to disable the speaker. BIOS is very limited in my laptop, that was my first idea too but I can't use it for virtually anything. I'll see if anything I can do from the desktop makes any difference, and if not, I guess I'll leave it in the hands of a repair shop and ask the guys to either fix or disable the speaker.

You've been a huge help, I'd probably still be convinced that it's the fan if it wasn't for you.

I'll leave another reply when or if I manage to actually fix this. And if some other ideas are out there, I'd appreciate them as well.