Welcome to the MacNN Forums.

SalBaker · Jun 12, 2005, 05:54 PM

Has anyone had success getting Apple to fix the noise in the 2.3 or 2.7 PMs?

IcedOrange · Jun 15, 2005, 09:06 AM

My brand new Dual 2.3 'chirps' when I resize windows, drag windows, etc. I've read about the CHUD tools NAP fix, but I hear it's "not reccomended" by Apple. I guess I'm also in the same boat looking for a permament fix.

voo · Jun 15, 2005, 02:45 PM

This chirping thing, does it actually come from the tower itself or is it a beeping sound through wav files or something like that on the desktop?

IcedOrange · Jun 15, 2005, 02:51 PM

It sounds like an electronic chirping sound that emits from the tower everytime certain actions are performed. It does not make the sound when the computer just sits there idle.

Skypat · Jun 16, 2005, 08:26 AM

There is also a pulsing sound that comes from my G5 dual 2.3. It is not loud but quiet annoying.

jamil5454 · Jun 16, 2005, 08:54 AM

I believe this is an issue on most if not all PM G5s. From what I read online, it's the power supply that's making the noise, and it's caused whenever you have Nap mode on. Nap mode allows the processor to sleep whenever it has an idle cycle.

Now, the chirping noise only seems to appear whenever you resize a window, scroll a window, do anything OpenGL, etc, so I believe it might have something to do with the way the CPU and video card interact.

All I know is that the chirping noise is evident on my week-old DP 2.0 rev.C. Downloading CHUD tools and unchecking the Allow Nap box fixed the noise, but it didn't stick on a reboot, and isn't recommended by Apple. For now, I put my PowerMac on the floor next to my desk, and I really can't hear it unless it's in the dead of the night. But when I can hear it, it's like there's a little kitten scratching subtly on my ear drums, if that makes any sense. In other words, it gets very annoying, very fast. And this is coming from someone who switched from a (very!) noisy Athlon64 box. But other than that, my G5 is nearly silent.

d.fine · Jun 16, 2005, 09:00 AM

My RevB DP2.0 rarely has it. sometimes when playing QT movies in the preview column. But it has been a while now since I heard a chirp come from it. Nothing has been changed.

Nugget · Jun 17, 2005, 11:15 AM

I'm not convinced that it's quite as simple as just a power supply defect. My new PowerMac didn't chirp at all, but then I had to get the mainboard replaced by AppleCare and now it does. Same power supply before and after.

The chirps seem related to bus activity, specifically when the video card is moving lots of data. The RSS screen saver makes it chirp, or playing games in full screen mode. Less so with windowed tasks, although even then sometimes it chirps a bit if the window is "busy". (World of Warcraft, in particular)

It's a quiet noise that you might not even notice, but it's hard to not focus on it after it bugs you the first time. I just use the "NAP" trick whenever I'm about to do something that I know will make it chirp. It's easy to enable/disable NAP via applescript, which is simpler than launching CHUD Tools all the time.

RevEvs · Jun 17, 2005, 11:47 AM

FYI, my friends PC also chirps. Seems to be gfx related - so any time you resize a window etc...

David Thompson · Jun 17, 2005, 04:00 PM

I just got my PM dp2.0 yesterday. No chirping that I can detect. I've got the unit on the floor, but fairly close by. The only thing I hear are the disk drives accessing.

(I sure had a LOT of difficulty installing RAM modules! Had to reseat them three times before the system saw them. Not a lot of room in there for hands, either.)

nycdunz · Jun 17, 2005, 05:06 PM

its the cpu, it happens on my powerbook also...

Skypat · Jun 17, 2005, 06:53 PM

And can you hear a pulsing sound that comes (I am not sure) from the 2 main fans in front of the processors ? It makes a kind of "woo woo woo" sound ...

d.fine · Jun 18, 2005, 02:57 AM

Originally Posted by David Thompson

(I sure had a LOT of difficulty installing RAM modules! Had to reseat them three times before the system saw them. Not a lot of room in there for hands, either.)

You did take out the intake fans I hope, there's plenty of room, and it should be fairly easy to install...

David Thompson · Jun 18, 2005, 07:22 AM

Originally Posted by d.fine

You did take out the intake fans I hope, there's plenty of room, and it should be fairly easy to install...

Yes. But I have big hands ...

jhogarty · Jun 18, 2005, 07:59 AM

I've been having the chirping also. Got my PM last week. I'll be more aware now but I really notice it while playing WoW (World of Warcraft).

Nugget - I'm new to the Mac, how do you do an Apple Script to turn off Nap? (And back on I would assume). Also was wondering if when you play WoW if it is laggy. Game looks beautiful on my 23" ACD but laggy. I've tried tweaking the video settings but doesn't help.

J.

jamil5454 · Jun 18, 2005, 08:28 AM

You'll need a hefty video to run WoW successfully at higher settings.

Anyway, I also think the chirping is graphics-bus related. Does anyone know exactly what disabling NAP does? That solves the problem for me, but if it means that my PowerMac might run hotter or make my electric bill go up noticeably then I can live with the chirping. I just might take it in to the Apple Store soon and see if they can do anything about it.

jhogarty · Jun 18, 2005, 12:35 PM

I talked with two guys today at the apple store. A sales guy and one of the genius bar guys. They both said they have never heard the "chirping" before. They gave some things to look at but I had already checked those things out. They asked me to try to narrow down when it occurs and maybe lug in my PM.

What type of hefty video do I need? I have the ATI Radeon 9600XT with 128MB VRAM. And my system is running 2.5GB of RAM. My laptop only has a 64MB video card and a gig of ram. I only lag when on dial up.

J.

ae25 · Jun 18, 2005, 01:06 PM

Just found this out and thought it was kind of strange. I was playing WoW and put it in windowed mode (command + M), and the chirping is not nearly as loud or as frequent in windowed mode. Also, sometimes when I have another window other than the WoW window active, the chirping goes away, and then as soon as I click on the WoW window, the chirping comes back, even though the WoW window is still fully visible, just not active. This would lead me to believe that the chirping is related to graphics, and can be fixed.

jhogarty · Jun 18, 2005, 02:43 PM

I just finished a two hour WoW session and the chirping was going on almost the whole time. Now with it closed and just Firefox up, the sound is gone. Looks like it is graphics related or at least when the computer is crunching away. Going to do some Photoshop and test renders in Lightwave to see if it chirps then.

J.

UnixMac · Jun 18, 2005, 05:24 PM

My chirping sounds more like a hamster wheel with the hamster going full bore on it! It gets quite loud at times, and has nothing to do with intensive apps like Doom 3...

I called Apple care twice on it, all they could say is to take it into the local service center... hate to do that without a definite fix in mind first though!

Nugget · Jun 18, 2005, 06:29 PM

I've got the GeForce 6800 Ultra card and WoW beautiful and smooth in 2560x1600 on my 30" cinema display with all the settings cranked to the maximum. On my old PowerBook G4 I have to minimize all the graphics settings to the bare minimum and even still it's kind of choppy at times.

It's possible to enable or disable NAP from the command line or from an applescript. In Terminal.app you can run the command using true or false as required:

Code:
hwprefs cpu_nap=true

Similarly, you can do this inside applescript (fire up Script Editor and create a new applescript):

Code:
do shell script "hwprefs cpu_nap=true"

I've got two applescripts "Silence" and "Squeal" that I launch from quicksilver before I play WoW (or any other activity that pushes a lot of graphics data across the bus)

jhogarty · Jun 18, 2005, 09:35 PM

Thanks Nugget I'll give that a try. I'll look into the GeForce card you have. I'm running the 23" ACD. I ran several renders in Lightwave and did some Photoshop work and no chirps. Going to hit WoW again.

J...

Groovy · Jun 19, 2005, 01:59 AM

Originally Posted by SalBaker

Has anyone had success getting Apple to fix the noise in the 2.3 or 2.7 PMs?

Yes. For me it was an easy fix. Every time i did anything graphic like resize a window
which heats up the GPU on your video card fast the fan in the front of that air flow section
would spin up and then Chirp Chirp Chirp. Thing is since most everything i do and a lot
of what OSX does, pushes the video card so i had a lot of chirping.

So i call Applecare and tell them I want it fixed and the person is like well chirping noise
is not exactly something we cover. some people just are overly sensitive to certain sounds.
I laugh and say "Oh really well how about I hold the phone in front of my G5 and you
listen and tell me if you think nothing is wrong"

So i hold the phone right in front of the fan grill area that is chirping like crazy and the
Applecare person says "Oh my! that is horrible! Ok that is not normal you should take it in
to get fixed and it will be covered under applecare" I say I know exactly what the
problem is and it is a user replaceable part. I just need you to send me that part.

So she does and overnights it even for free. I get the new fan and it takes just minutes to
swap out and that is the end of the chirping and has not returned and that was months
and months ago.

Turned out to be the fan bearings were packed too tight and it is a problem with
many of the fans Apple used from the company that makes them for Apple.

Good luck in getting yours fixed

sheer · Jun 19, 2005, 06:49 AM

My Rev B dual 2.0 made a high pitch whine when transferring stuff over FTP on the home network but upgrading to Tiger fixed that. Go figure.

Nugget · Jun 19, 2005, 07:07 AM

Originally Posted by Groovy

Turned out to be the fan bearings were packed too tight and it is a problem with
many of the fans Apple used from the company that makes them for Apple.

I'm glad your issue turned out to be simple to fix. The "chirping" noise that many of us experience (which can be silenced in software with NAP mode) is not so simple, though. It's definitely not a fan bearing making the noise, and it's not related (that I can tell, at least) to any moving part. It seems to be some weird sort of interference caused whenever high volumes of data are being shuffled around inside the machine.

My TiBook made a similar noise, also during periods of intensive video activity.

UnixMac · Jun 19, 2005, 09:35 AM

We must be talking about two types of noise here, as I'm sure mine is mechanical, more like what Groovy described. I also called Apple care and had them listen to it, and they said to bring my G5 into a service center.. not! Which fan exactly did they replace for you Groovy? The two removable ones that sit infront of the PCI cards?

jhogarty · Jun 19, 2005, 09:46 AM

I tried to do the scripts you suggested and they wouldn't run. Then I realized I didn't have CHUD installed so I grabbed that and the scripts ran fine. By fine I mean they executed without errors. I had:

[Silence Script, as an app]
do shell script "hwprefs cpu_nap=true"

[Squeal Script, as an app]
do shell script "hwprefs cpu_nap=false"

I ran Silence and still had the chirp. Then I thought about those lines and thought they should be reversed. So I changed the scripts to this:

[Silence Script, as an app]
do shell script "hwprefs cpu_nap=false"

[Squeal Script, as an app]
do shell script "hwprefs cpu_nap=true"

Re-ran WoW and the chirps are gone. Like I said I'm new to this but thought I would post in case anyone else is/wants to try this as a solution.

Thanks again.

J.

Groovy · Jun 19, 2005, 04:41 PM

Originally Posted by UnixMac

We must be talking about two types of noise here, as I'm sure mine is mechanical, more like what Groovy described. I also called Apple care and had them listen to it, and they said to bring my G5 into a service center.. not! Which fan exactly did they replace for you Groovy? The two removable ones that sit infront of the PCI cards?

I had them send me a new fan and it was easy to swap out myself.
It was the front fan with the internal speaker connected to it that sits in the
PCI/AGP section and is about 1 inch from the front grill. It is just one fan not two.

this fan (page 7 has a great pic of it)

http://manuals.info.apple.com/en/PMG...er:Fan_DIY.pdf

Groovy · Jun 19, 2005, 05:15 PM

Originally Posted by Nugget

I'm glad your issue turned out to be simple to fix. The "chirping" noise that many of us experience (which can be silenced in software with NAP mode) is not so simple, though. It's definitely not a fan bearing making the noise, and it's not related (that I can tell, at least) to any moving part.

Well i used to think that also but putting your mac in nap mode may throttle the CPU
or other components just enough so that not as much heat is made and thus no chirping
from slower running fan. The thing is when i say chirping i truly mean chirping as if a
tiny bird was chirping. (I wish i saved the the sound recording i made of it)

What are the odds that 2 different things, one mechanical and one not, make
the exact same sound that can only be described as chirping? Is your sound a
sound that chirping best describes it or not? (my sound sure was)
A recording posted here would be nice and I could tell you at least if it was what i heard.

BTW - Why haven't you located the exact sound source? You should have no problem
finding exactly where the sound is coming from be it power supply, fan, or
whatever. (at the very least which air flow section it is coming from)

Originally Posted by Nugget

It seems to be some weird sort of interference caused whenever high volumes of data are being shuffled around inside the machine.

My TiBook made a similar noise, also during periods of intensive video activity.

And what you say above means more heat via higher CPU loads and other components
to move all that data and the TiBook same thing, as well as higher GPU load. The fans
could very well be running faster.

Anyway, I hope you figure it out and get it fixed so everyone else can too.

Nugget · Jun 19, 2005, 09:16 PM

It is not a fan. I don't know how to say it any more plainly.

Todd Madson · Jun 19, 2005, 10:18 PM

My G5 2.5 dual has never exhibited any of this behavior. Strange.

loki74 · Jun 20, 2005, 02:00 AM

My dual 2.5 makes a noise when I scroll, Expose, drag, resize, etc. I never really though to call it "chirping," though. I was actually planning to post something here once I found an adequate word to describe it... I guess "chirping" works, but it is not literallly like a bird chirping, and I dont think it could be heard if I held a phone up to it. Its actually very subtle, but really weird, and it comes and goes from time to time. I think maybe it is the sound that the Applecare lady said that certain people are too sensitive to in Groovy's experience.

Then again, with my G5 on the desk, its just a little over a foot away from my head... I guess if I get a stand and move it to the ground, I probably wont hear it; like I said, its really subtle. Even if I wont die not having a solution, it would be nice to know exactly what the sound is, I dont think its physical, but I know for sure that its not a sound effect that was made on purpose.

RevEvs · Jun 20, 2005, 09:59 AM

Originally Posted by Nugget

I've got the GeForce 6800 Ultra card and WoW beautiful and smooth in 2560x1600 on my 30" cinema display with all the settings cranked to the maximum. On my old PowerBook G4 I have to minimize all the graphics settings to the bare minimum and even still it's kind of choppy at times.

It's possible to enable or disable NAP from the command line or from an applescript. In Terminal.app you can run the command using true or false as required:

Code:
hwprefs cpu_nap=true

Similarly, you can do this inside applescript (fire up Script Editor and create a new applescript):

Code:
do shell script "hwprefs cpu_nap=true"

I've got two applescripts "Silence" and "Squeal" that I launch from quicksilver before I play WoW (or any other activity that pushes a lot of graphics data across the bus)

Down suppose theres a similar command for setting processor performance (Lowest, Automatic, Highest)

?

jamil5454 · Jun 20, 2005, 10:03 AM

It can barely be described as chirping, but it's more like very high pitched fast pulses/whine that occurs whenever a lot of data is moving across the graphics bus. It kinda sounds similar to that high pitched whine emitted by a TV when you first turn it on.

Some people may not be able to hear because the frequency is too high, but for those that can hear it it gets really annoying, really fast.

It's definitely more of an electronic sound, not mechanical.

jhogarty · Jun 20, 2005, 11:48 AM

Just noticed I get the "chirping also when resizing windows. It is much fainter than when I play WoW. If use the scripts Nugget suggested the sound goes away.

My only question I guess is, what impact is there to the computer if I set cpu_nap=false (ie. stop the squeak)?

The sound it makes other than when playing WoW is not bad. I hardly notice it. But it is very annoying and irritating when playing WoW. It is much louder and constant. Sometimes I just turn up the sound to wash it out. But at night I need to lower so I don't wake the kids. :-)

J...

Groovy · 05:54 PM

Originally Posted by Nugget

It is not a fan. I don't know how to say it any more plainly.

I didn't say it was a fan on your box. I will repeat what i said

"Why haven't you located the exact sound source? You should have no problem
finding exactly where the sound is coming from be it power supply, fan, or
whatever. (at the very least which air flow section it is coming from)"

To use YOUR words. I don't know how to say it any more plainly. lol

"power supply, fan or whatever" Not plain enough for you? You only saw the word "fan"?

You never answered why you haven't located the exact sound source.
So what is the exact sound source of this chirping? You are sure it is not a fan, great!

So what is the source?

Just take the side cover off then tilt the plastic cover until it is almost level with desktop
but keep the bottom tabs in the G5. This keeps the switch pressed so the fans will not
REV up etc... If you go too far you hear them REV up and a red light will turn on and you
will not be able to hear anything but the fans at full blast. Anyway plenty of room for you
to stick your ear next to all components and find the exact chirping source in under 30
seconds which is all i did to find the exact sound source.

good luck

Groovy · Jun 20, 2005, 05:42 PM

Originally Posted by jamil5454

It can barely be described as chirping, but it's more like very high pitched fast pulses/whine that occurs whenever a lot of data is moving across the graphics bus. It kinda sounds similar to that high pitched whine emitted by a TV when you first turn it on.

Some people may not be able to hear because the frequency is too high, but for those that can hear it it gets really annoying, really fast.

It's definitely more of an electronic sound, not mechanical.

Well this noise I heard in no way could you say it was electronic or mechanical.
It could have been either. i thought it was electronic until I decided to find the
exact source of the sound.

Anyway what you describe doesn't sound like chirping.
at least not the chirping I had. Mine was really like chirping. In fact there
was a toy years ago i saw that is a simple 2 piece thing where 1 plastic thing the
size of ones pinky with a ring on the end slides inside a plastic tube. When you
spun the ring the plastic parts rubbed against each other and made a chirping
sound. Well same sound i heard. Not as loud or sharp but same kind of sound.
And it turned out it was the bearings and friction related on my fan so sorta
the same concept i guess lol

jamil5454 · Jun 20, 2005, 06:13 PM

I've heard noisy computer fans, and this is definitely not the same thing. The noise will be totally synchronized with the movement of your mouse if you're doing something that causes it (resizing, scrolling, etc).

It can sort of be described as something you might not hear, but once you notice it, it sticks out like a sore thumb. When I first heard it, I couldn't tell where in my room it was coming from. It's a kinda "where am I" type of high pitched soft sound, similar to a random out-of-nowhere ringing you may get in your ears, but not as loud. I would try to record the sound, but I'm almost positive the microphone wouldn't be able to pick it up. That's as best as I can describe it.

Nugget · 09:42 PM

Originally Posted by Groovy

You never answered why you haven't located the exact sound source.
So what is the exact sound source of this chirping? You are sure it is not a fan, great!

I didn't see any value in sending the discussion in that direction. It seems to me that you're pretty sure I'm wrong, but I don't mind that you think that. I'm happy for you that it was just a fan in your case.

In any event, I've tried plenty of times to localize the noise with no luck. It's such a high pitched nails-on-chalkboard squeal that it's just not possible to tell where exactly it's coming from. I also think that the "odds" are 1 in 1 that we're talking about two different symptoms and two different issues.

In the interests of better understanding I did take the time to record a little movie that demonstrates both the noise and its responsiveness to "NAP" and video activity. Perhaps this will make the situation more clear to those who are not experiencing this noise on their machines.

For your viewing pleasure:
G5 Squeal (Quicktime, 10MB)

Cheers

jhogarty · Jun 20, 2005, 10:01 PM

That is exactly what goes on with my box. I have the exact same results when I use the scripts you suggested.

By the way, what realm you play on? Horde or Alliance?

J...

loki74 · Jun 20, 2005, 11:56 PM

i think jamil has what i'm talking about here.. certainly not mechanical...

jamil5454 · Jun 21, 2005, 12:26 AM

Originally Posted by Nugget

I didn't see any value in sending the discussion in that direction. It seems to me that you're pretty sure I'm wrong, but I don't mind that you think that. I'm happy for you that it was just a fan in your case.

In any event, I've tried plenty of times to localize the noise with no luck. It's such a high pitched nails-on-chalkboard squeal that it's just not possible to tell where exactly it's coming from. I also think that the "odds" are 1 in 1 that we're talking about two different symptoms and two different issues.

In the interests of better understanding I did take the time to record a little movie that demonstrates both the noise and its responsiveness to "NAP" and video activity. Perhaps this will make the situation more clear to those who are not experiencing this noise on their machines.

For your viewing pleasure:
G5 Squeal (Quicktime, 10MB)

Cheers

Looks like you proved me wrong about the noise not being able to be recorded. The noise CAN be recorded obviously (apparently with a good microphone, too), and this is EXACTLY what my PowerMac exhibits. I can usually only hear the squeal when everything is quiet, but when I do hear it, I can't take my attention away from it.

So, who else gets this? Hopefully Apple can fix it via a software update so I don't have to take my machine into the local Apple Store. Come on Apple! You can do it!

loki74 · Jun 21, 2005, 01:08 AM

yes that is exactly the thing!

Todd Madson · Jun 21, 2005, 07:16 AM

WOW. I watched that video and not only is that squeal annoying but your Mac is so loud
I cannot believe it. Mine is so quiet I can hardly tell that its on unless I look at the front
panel. Somethings' gotta be wrong there.

jamil5454 · Jun 21, 2005, 07:50 AM

I don't really think his mac is that loud, it's just that he's got the microphone right up to the front grill, and he's playing a game. But you can definitely hear the squeal. Thanks Nugget for finally clearing this up!

Nugget · Jun 21, 2005, 07:58 AM

Yeah, that video was shot with a microphone placed just an inch or two away from the front grill of the machine (see the little inset photo in the clip). Your Mac would be just as loud if you wore it like a hat!

d.fine · Jun 21, 2005, 07:59 AM

When I ocassionally get the squeal it is not that loud. I've not had a squeal moment since 10.3.8 I think...
My G5 sits 30cm from my head on the desk...
I agree that the mic is very close to the G5 PSU, if I put my head there I hear a lot more of the machine than usual, which is not surprising.

Also seems that when you disable NAP the fans speed up, so the CPU's are heating up a lot faster all of the sudden?

Nugget · Jun 21, 2005, 08:29 AM

As soon as I disable NAP the fans spin a little bit faster for two or three seconds, then they drop right back down to their normal slow (and practically inaudible) speed.

jamil5454 · Jun 21, 2005, 08:56 AM

Nugget, I don't mean to hijack the thread, but where in Austin do you live? I just moved here for school, down by Riverside Drive and Congress. On Thursday I've got a job interview at the Barton Creek Apple Store, and they're looking to hire about 10 people. If I get it that would Rawk.

But who cares?

Nugget · Jun 21, 2005, 11:14 AM

I'm in northwest Austin, up by 183 and Anderson Mill Road. "South Dallas" if you ask folks from south of the river.