Coil Whine randomly started?

[RedlineGamer2005]

Hello! I recently started experiencing a slight coil whine on my laptop. I don't really know why it has started and needed some help figuring it out. So I came here!
My laptop is a Lenovo legion Y540 btw. I recently repasted my CPU and GPU since temps were getting out of hand. It didn't give much of an improvement so I'm not sure whether I shud check the spread of the repaste by removing the heatsink again. Maybe that could be answered by one of many experts on here. After putting everything back together pretty well, I started noticing a slight coil whine. Note I haven't touched anything but the heatsink which comes off using a couple of spring-loaded screws. What is the cause of this? Can it be fixed? Is it harmful to the system?

 

[Bill_Bright]

I recently repasted my CPU and GPU since temps were getting out of hand. It didn't give much of an improvement

No surprise you got little improvement. There very rarely is any need or benefit to re-applying the TIM (thermal interface material) because it just doesn't go bad. It will easily last many many years AS LONG AS the cured bond between the mating surfaces is not broken.

Even if the TIM has dried out, the solids that are left behind are still occupying the microscopic pits and valley and doing their job - preventing insulating air from getting in there. So even if dried, there's no need to replace it.

If the system "needs" the few degrees a fresh application of TIM might provide to keep from crossing over thermal protection thresholds, there are bigger problems to deal with first - like case cooling, dust buildup, fan control, etc.

There is actually greater risk of damage due to accident, mishandling and/or ESD when redoing the TIM. For these reasons, it is typically best to just leave it - again as long as the cured bond remains intact.

That said, if done carefully and properly, there is no reason applying a fresh new layer of TIM would cause coil whine. So are you 100% sure it is coil whine you hear? If it was not there before redoing the TIM and appeared right after redoing the TIM, I would suspect something is interfering with the fan blades.

As far as being harmful, coil whine is not. But it sure can be annoying. If something is interfering with the fan blades, that can be a problem. It can reduce cooling efficiency. And if a blade is scraping a wire, it might eventually wear down the wire's insulation and expose the bare copper. That's not good either.

 

[TheUn4seen]

As for the paste, Y540 is kind of toasty and has very little thermal capacity, so don't expect miracles. Coil whine often starts after a certain time of using a device - days, months. Since it actually is caused by physical motion of components in high frequency circuits (i.e. coils in power delivery, backlight inverters and such, but many components can actually be the source, like ceramic caps), they can work themselves looser over time and gradually become louder. It sure is annoying, but not dangerous or harmful to anything other than user's sanity. There is not much that can be done about it from the user's perspective.

 

[Bill_Bright]

There is not much that can be done about it from the user's perspective.

This is true - however, sometimes, if it really is "coil" whine (or transformer plates vibrating), a dab of hot glue or epoxy glue on the coil windings or transformer plates can stop them from vibrating. But it is not always easy to find or access the exact spot to apply that glue. And this trick is not always lasting.

 

[jboydgolfer]

its not a laptop, but my daughter called me to her room the other day, while she was playing sim3. she told me she was hearing a strange noise from her PC. it was coil whine. i had her leave the Sims 3 loading screen on & 30 minutes later, it was gone. hot Glue as mentioned can help too, if it is indeed coil whine.

 

[TheUn4seen]

This is true - however, sometimes, if it really is "coil" whine (or transformer plates vibrating), a dab of hot glue or epoxy glue on the coil windings or transformer plates can stop them from vibrating. But it is not always easy to find or access the exact spot to apply that glue. And this trick is not always lasting.

As a silence-loving freak I am guilty of using epoxy to silence several devices. It really is tricky to find the offending component, also, it can cause thermal issues - consumer electronics are really built down to a price, and insulating a tiny capacitor or a coil with epoxy can cause it to fail prematurely. That's why I wouldn't recommend users do this unless it really is a last resort or a device the user doesn't value a lot.

 

[Bill_Bright]

and insulating a tiny capacitor or a coil with epoxy can cause it to fail prematurely.

That's why I wouldn't recommend users do this unless it really is a last resort or a device the user doesn't value a lot.

Ummm, I never said to "insulate" the offending device. That would be silly.

I specifically said to use a "dab" of glue on the device, at the "exact spot" where the vibration occurs.

That said, dipping in or coating the entire coil or transformer with epoxy resins is exactly what they typically do at the factory. And what typically happens is there is a thin spot, or a bit of resin, being brittle once cured, flakes off and that is where the vibrations occur.

As far as being a last resort - assuming the circuit is working with normal parameters, there is no other option but to live with the noise, or replace the entire device.

 

[RedlineGamer2005]

No surprise you got little improvement. There very rarely is any need or benefit to re-applying the TIM (thermal interface material) because it just doesn't go bad. It will easily last many many years AS LONG AS the cured bond between the mating surfaces is not broken.

Even if the TIM has dried out, the solids that are left behind are still occupying the microscopic pits and valley and doing their job - preventing insulating air from getting in there. So even if dried, there's no need to replace it.

If the system "needs" the few degrees a fresh application of TIM might provide to keep from crossing over thermal protection thresholds, there are bigger problems to deal with first - like case cooling, dust buildup, fan control, etc.

There is actually greater risk of damage due to accident, mishandling and/or ESD when redoing the TIM. For these reasons, it is typically best to just leave it - again as long as the cured bond remains intact.

That said, if done carefully and properly, there is no reason applying a fresh new layer of TIM would cause coil whine. So are you 100% sure it is coil whine you hear? If it was not there before redoing the TIM and appeared right after redoing the TIM, I would suspect something is interfering with the fan blades.

As far as being harmful, coil whine is not. But it sure can be annoying. If something is interfering with the fan blades, that can be a problem. It can reduce cooling efficiency. And if a blade is scraping a wire, it might eventually wear down the wire's insulation and expose the bare copper. That's not good either.

Im pretty sure it is coil whine. About the fans, I'm not really sure wether its really the fans because when I open a game(for eg. Valorant) the CPU doesn't instantly sort off kick in and start the fans too, it takes a few seconds right? within those few seconds I can hear some sort of buzz which I'm pretty sure has to be coil whine. If it isn't harmful then I don't really mind since I use headphones all the time anyway

As for the paste, Y540 is kind of toasty and has very little thermal capacity, so don't expect miracles. Coil whine often starts after a certain time of using a device - days, months. Since it actually is caused by physical motion of components in high frequency circuits (i.e. coils in power delivery, backlight inverters and such, but many components can actually be the source, like ceramic caps), they can work themselves looser over time and gradually become louder. It sure is annoying, but not dangerous or harmful to anything other than user's sanity. There is not much that can be done about it from the user's perspective.

True this laptop is the hottest i have ever had. Not buying a laptop again tho. Although they say its portable and stuff, unless u undervolt and have the CPU run at 1.2Ghz and lower this things battery dies in less than 4 hours which means I have to take the big ass charger everywhere which defeats the whole purpose of a "portable" laptop. I wish I had known before spending this much on this laptop. I gotta say tho the performance is really phenomenal. I get like 90FPS in warzone with everything set to max

 

[Jose Jeswin]

did you check the speakers?....

a buzzing sound can be static due to an improper ground..

 

[Bill_Bright]

You might be able to use a paper towel tube as a stethoscope and listen to hear if you can pinpoint the source. And Jose has a good suggestion to make sure it is not coming from the speakers instead - though I would think you would hear that in your headphones too in that case.

 

[RedlineGamer2005]

You might be able to use a paper towel tube as a stethoscope and listen to hear if you can pinpoint the source. And Jose has a good suggestion to make sure it is not coming from the speakers instead - though I would think you would hear that in your headphones too in that case.

Yes, they are for sure not the speakers. Also I repasted my laptop and that requires me to open it up and remove the heatsink. the laptop is made in a way by which i didn't need to touch any electricals which means that I did not bring about the coil whine with that. Any fixes for it?

 

[Bill_Bright]

I already made my suggestion but even that will not work if you cannot isolate and identify the specific component.

 

[Jose Jeswin]

I would try one more thing...with the laptop switched on, i would hold the laptop in different orientations to check if the coil whine goes away..that would surely identify it as a loose component..and then try to identify it..