Thinkpads Forum

Hi!
I am encountering a high frequency which definitely comes from the fan: It's immediately gone when I turn the fan off. It's not very loud and extrem constant, but it is nevertheless annoying when you are in a silent environment...
Has anybody the same fan frequency?
I will try to make an audiofile...

I get this too, and although it's not very loud, I find it more distracting than a typical fan sound that may be slightly louder.

One of my T60's had that problem. I took a small plastic tool and slightly adjusted the "gills" - the thin metal air guides inside the rear exhaust vent - and the problem went away. I think that one of the blades was angled just right to make a whistling when the fan was on.

Are you talking about the big gills on the outside or the smaller ones which you can see behind the big ones?

here is my sound file...
http://www.flob.de/pitch.mp3

*bumb*
No more answers? Does that mean your fan doesn't make such a noise?
Thanks for any comments!

squashball wrote:Are you talking about the big gills on the outside or the smaller ones which you can see behind the big ones?

The small metal ones

RonS wrote:

squashball wrote:Are you talking about the big gills on the outside or the smaller ones which you can see behind the big ones?

The small metal ones

Of course the metal ones
But the first metal ones whicht can be reached from the outside and not the small ones which you can see behind the big ones, right?
I tried your advice, but the sound seems not to be generated by these big gills

Does it sound the same at all fan speeds?

No, it's going proportional, as you can hear in my MP3 file: By the first click sound (tmpfancontrol), the fan speed is going from 3 to 5 and the noise is increasing, too.

squashball, others...

Today I noticed this sound too, before reading your post. Thank you for posting that link to your recording, btw. It is extremely helpful to have some real data to work with instead of the far more common literary descriptions of any of the numerous sounds our little boxes produce.

The sound I am hearing is of nearly the exact same frequency, as far as my ears can tell to the one in your recording. I also noticed a bit of a pulsing nature to it as well and was able to correllate that sort of whining, pinging sound with the update interval for the fan speed as changed by the embedded controller. It takes right around five seconds for the EC to complete a fan speed poll-and-adjust cycle it seems and right when the EC updates the fan speed that little pinging modulation happens in the constant high-pitched whine.

I tried poking around with a pen cap at the copper heatsink vanes in the hope that it was an air whistle but was unable to eliminate the sound. Admittedly, I didn't jab around too hard, so I might not have even changed anything in there. I may try again if this sound persists. I do know what you mean about it being annoying though. It isn't terribly apparent unless you are in a very quiet room and because it is such a high frequency it tends to tire the ears. It's very noticeable when the computer powers off, the fan stops, and glorious silence ensues. I'll let you know if anything I do helps dampen this sound.

Thanks, Omou!
I agree that the sound isn't too bad and only noticable in a very silent room.
BUT my T60 (UT063) has cost me about 2000Euros (~2 500Dollars) and I am not willing to accept that!
I will call the service today and try to eliminate the problem...

..just finished the call:

Op: "Make a BIOS update and the noise is history"
Me: "No, it is definitely the fan, what you mean is the problem with the powersave mechanisme of the cpu! I fixed THAT problem by turning off the poersaving cpu stuff in the BIOS."
Op: "Oh, ok"




I am going to send the whole stuff back and they will have a look at it. Unfortunately, that means erasing the disk

I really hope that they will not send it back to me with comments like "we can't hear anything" or "fixed" (but nothing done)...

Let us know what happens. I'm thinking about doing the same thing. You should be able to pull the hard drive and keep that with you right? They don't need it to diagnose the problem.

I'm going to be using the T60 in a classroom so a high pitching whine is a no-no unless I want some nasty stares.

I was told to send the whole paket back, for the case they have to swap my machine with a new one...
On the one hand I didn't understand that, but on the other hand I will put a note, that in case they can't hear anything, they can keep the notebook and I will use my 14 days warranty

RonS,

Did you have a chance to listen to squashball's audio file? Did your high-pitched noise sound exactly like that? I'm just trying to gauge how likely it is that I'll be able to eliminate this frustrating sound on my own without sending the unit back for repair. I'm hoping this sound is in fact due to some kind of whistle from air motion and not something inherent in the sound of the fan rotating or the bearings or whatever mechanism it uses. But since squashball's audio sounds exactly like the same sound my fan is making, it seems a bit unlikely that a random air whistle would make that exact same sound, thus suggesting something inherent in the rotational mechanism of the fan itself.

Oy. I should have listened to louder music when I was younger...

I tried to cover (alternating) one of the two fan slots with my hand to figure out which gills make the noise. (With the idea that the covered gills will not be able to oscillate with no air comming through) But that didn't elliminate the noise and I reasoned that the gills are not my problem...

squashball wrote:I tried to cover (alternating) one of the two fan slots with my hand to figure out which gills make the noise. (With the idea that the covered gills will not be able to oscillate with no air comming through) But that didn't elliminate the noise and I reasoned that the gills are not my problem...

LOL, no I don't think that the airflow could even go through there fast enough to start oscillating the vanes. That would have to be an impressive airflow for sure; by that time, you would be hearing the airflow way more than any vibrations the vanes produced.

I was talking about that

One of my T60's had that problem. I took a small plastic tool and slightly adjusted the "gills" - the thin metal air guides inside the rear exhaust vent - and the problem went away. I think that one of the blades was angled just right to make a whistling when the fan was on.

And I wasn't talking about the vanes!
Sorry for the "oscillating" - maybe the wrong term

Omou wrote:Oy. I should have listened to louder music when I was younger...

Oh, I have done that...It doesn't have as many benefits as it would first seem.

My guess is that the noise is mechanical in origin; partly because mre than just one system is reported to emit the sound and partly because it would either have to be a very obtuse protuberance in the path of the majority of the airflow or a very fast moving stream of air to cause an equivalent high pitched noise (unlikely).

Omou wrote:RonS - Did you have a chance to listen to squashball's audio file?

Yes I did, and that's exactly what my whistling sounded like. I fixed it by adjusting those small metal "gills" inside the rear fan exhaust.

RonS wrote:

Omou wrote:RonS - Did you have a chance to listen to squashball's audio file?

Yes I did, and that's exactly what my whistling sounded like. I fixed it by adjusting those small metal "gills" inside the rear fan exhaust.

Hm, I played a lot with those gills, without any effect.
What about you, Omou?

That sound definately has a mechanical origin. The airflow can mostly generate low frequency components. That would be also annoying, thou.

My guess is that this noise is an oscillation as some have called it, or more accurately the term is "resonance". I think the noise is coming from the fan motor itself, caused by the T60's speed control mechanism. Speed control is almost certainly "PWM" or pulse width modulation. If the modulation frequency is just right the motor mechanicals may be ringing like a gong or tuning fork would. If this si the case it may be possible to fix the issue with a keybord controller flash update. We'll see what Lenovo does about this

I agree. If that is the case, it may be solved with a bios update. though I must say, after the latest bios fiasco, I have doubts about lenovo's testing.

rvacha wrote:My guess is that this noise is an oscillation as some have called it, or more accurately the term is "resonance". I think the noise is coming from the fan motor itself, caused by the T60's speed control mechanism. Speed control is almost certainly "PWM" or pulse width modulation. If the modulation frequency is just right the motor mechanicals may be ringing like a gong or tuning fork would. If this si the case it may be possible to fix the issue with a keybord controller flash update. We'll see what Lenovo does about this

That is, most likely, the case; not quite resonance, but it is an approximation of PD control. It oscillates about steady-state if the gain is high enough.

Well, I tried all sorts of poking and prodding and listening, even to the point of adding some small pieces of tape to the inside of the case in places in the hope of adjusting the mass of any vibrating parts or disrupting the airflow to eliminate this sound with absolutely no luck. It does seem to be a sound instrinsic to the operation of the fan mechanism itself and thus I will probably not be able to do anything to silence it. As it is so irritating and would prove to be nothing but a severe aggrivation in a quiet setting like a library or just in a quiet room in my own place, not to mention bothersome to anyone within a surprisingly wide earshot, I have decided to forego any more tinkering and just have the machine serviced. I'll have to hold on to it for a week or so before sending it in to get some things done, but once I get it back, I'll post the result for those interested. With any luck they will replace the fan and the problem will be gone. The sound of rushing air is actually quite soothing compared to this and I look forward to hearing the cooling system on this machine pluckily (and quietly, or at least white-soundishly) pushing atmosphere around.

Extreme thanks to everyone who posted comments on this and for your insights into the source of this disturbance. May none of you ever be cursed with the Thinkpad "ping of insanity." Cheers.

I completely agree...
My T60 is on its way to the service...
I hope I will be able to post the result soon!

Just got a call...
The frequency is "in normal parameters"
In other words IBM/Lenovo is not able to produce/buy good fans
They offered me to order a new fan and send the notebook to me.
If I am not satisfied, I will still be able to send it back...
So far for my first "IBM THINKPADS ARE SOOOO GREAT" experience...

squashball wrote:Just got a call...
The frequency is "in normal parameters"
In other words IBM/Lenovo is not able to produce/buy good fans
They offered me to order a new fan and send the notebook to me.
If I am not satisfied, I will still be able to send it back...
So far for my first "IBM THINKPADS ARE SOOOO GREAT" experience...

Probably your first User Error experience too.