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shadewind

macrumors newbie
Original poster
Apr 16, 2010
15
0
In my brand new Mac Pro 8-core 2.4 GHz, there is a pulsing faint "howl". It sounds a fit like what's in the thread title.

Changing the exhaust or intake fan speeds changes the frequency of the pulsing so I suppose it must be some kind of resonance.

While it definately is something I can get used to, it would be nice to know if there is anything wrong with my Mac of if this is common.
 
In my brand new Mac Pro 8-core 2.4 GHz, there is a pulsing faint "howl". It sounds a fit like what's in the thread title.

Changing the exhaust or intake fan speeds changes the frequency of the pulsing so I suppose it must be some kind of resonance.

While it definately is something I can get used to, it would be nice to know if there is anything wrong with my Mac of if this is common.

Take it to Apple Store to replace the fan.
 
So is it a OOOOOoooOOOOoooooOO or more of a oooOOOOoOOOOOoOOOOO?

Seriously though, just take it in. First I'd use a little compressed air to clean the fans out to see if dust is the issue though.
 
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I'm not really sure I understand the difference between the sounds? :p

Anyway... Dust is not the problem, it's brand new after all and I can even see there's no dust.

Anyway, I've Googled a bit and noticed others having similar problems. Anyone who can comment?
 
Mine does the same resonating sound and I find it really annoying, too :/
I took mine into the Apple Store because of it (and because of a buzzing power supply), they gave it back to me saying there was nothing wrong and no repairs/replacements have been done... :mad:

I noticed that the intake fan (in my case) makes a big difference, I can actually wiggle it back and forth.. when I put my finger on it, the resonating sound changes/comes and goes, so I guess it's a vibration issue. Putting a piece of rubber in between the thin aluminium metal facing you (when looking at the intake fan) and the intake fan itself, took care of some of the vibration.
 
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Believe me, it's not a software problem. The fan spins just fine, it just sounds like some sort of acoustical or vibration problem to me.
 
Are you sure it's not hard drive vibration? In my case, a small rubber wedge under one corner of the Mac Pro minimizes the problem.

Swapping hard drive bays may also help.
 
Are you sure it's not hard drive vibration? In my case, a small rubber wedge under one corner of the Mac Pro minimizes the problem.

Swapping hard drive bays may also help.

If he has the same sound as me, it's most likely the intake fan and the processor cage causing the noise. I checked the hard drive bays first because it seems to be a common issue, but it's definitely not them in my case.
 
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I'm not really sure I understand the difference between the sounds? :p

Anyway... Dust is not the problem, it's brand new after all and I can even see there's no dust.

Anyway, I've Googled a bit and noticed others having similar problems. Anyone who can comment?
The P/N for the PCIe cooling fan assy changed for the 2010 systems. So I suspect that they with a different supplier and adjusted the specs a tad (went for a cheaper supplier that cut corners; the 2009 systems may have had ball bearings, now bronze bushings for example).

Assuming this is the case, the bearing has more "slop" to it, and is causing vibration. So as others have mentioned, take it in.

IF they won't help, you could order a fan unit from a 2009 system, and swap it out.
 
Could also be the Black. Mine makes enough noise that when it goes to sleep it's quite a difference.
 
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So you're saying it should ONLY be soft regular air noise? No kind of quiet ringing/pulsing tone?

Since I don't live in a country with Apple stores I'm nit sure how long such a repair would take... I need the machine for work after all.
 
So you're saying it should ONLY be soft regular air noise? No kind of quiet ringing/pulsing tone?
Just a whooshing sound of air moving.

Since I don't live in a country with Apple stores I'm nit sure how long such a repair would take... I need the machine for work after all.
Ouch. :(

Maybe you can get them to send the part to an Authorized Repair Facility if possible (they should have some sort of agreement near you), or directly to you, and install it yourself.
 
Just a whooshing sound of air moving.


Ouch. :(

Maybe you can get them to send the part to an Authorized Repair Facility if possible (they should have some sort of agreement near you), or directly to you, and install it yourself.

The retailer from which I bought it has Apple authorized service techs so they should be able to fix it. How does these things usually work? How long does it take? I can be without it for no more than a day or two.
 
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Believe me, it's not a software problem. The fan spins just fine, it just sounds like some sort of acoustical or vibration problem to me.

Probably some loose screws. Tighten stuff up and check again.
 
I called my retailer and they said that it'd take about a week to repair it... And I have recordings every weekend up until christmas...

Edit: Okay... Here's what I'll do... Finish all current projects and then turn it in. Don't really know when I'll get the time but I have Apple Care and all that so it's no hurry. I can live with it in the meantime since I always mix louder than that anyway.
 
Open the case up, see which fan it is?

Then using SMC Fan Control increase or decrease the RPM on that fan until it shuts up?

That's what I used to do with a old X1900XTX GPU fan I had.
 
LOL .............. Just started to get a low "growl" noise that comes and goes every 10 minutes or so. Definitely coming from one of the fans. Probably the processor fan but I'll do some investigation this weekend.

Edit: OK, I just isolated the intermittent low "growl" noise to the CPU fan. Just emailed the business manager at the local (Thousand Oaks) Apple store. This will be a good "test" for them. Let's see if I can maintain my "fan-boy" praise of Apple. :p

2nd Edit: The intermittent low growl hasn't shown it's ugly face in two days now. ??? I'm sort of inclined to leave sleeping dogs alone right now and not do anything about it. The slight growl was definitely coming from the CPU fan and I sort of expect it to return at some point. Will deal with it if/when it returns.

cheers
JohnG
 
@ OP
Out of curiosity please tell us your HD drives, RAID setup, & Bootdrive etc...

Stock WD 1TB drive plus a Samsung 500 GB drive. The sound is there regardless of whether the Samsung drive is installed and I seriously doubt the noise is coming from the WD drive since altering the fan speed alters the sound.
 
The repair can take a few minutes. Delivering parts can take longer, but as soon as they have parts swapping fans doesn't take that long. I took my Mac Pro to Apple Store on Saturday and they ordered a fan. I took it back with me. On Tuesday they called me that they got the fan and I can come over to swap it. And here they screwed up badly. They told me I don't need an appointment and it shouldn't take long to do it. Next day I came in at lunch (12) to do the repair. The guy, the "genius" told me that they are busy and I have to come back at 3 pm to pick it up. OK, fine. I got from work to pick it up. They told me that they need 45 min more to finish the repair. (What?) I am sure, they didn't even touched it. I can't go back to work because it would take me 30 min to return. OK, I am waiting... In 45 min I check with them and they are still not done, they replaced the fan and started some testing/diagnostic procedure. OK, when it is going to be done? -We don't know, should be soon... I check in 15 min. It is still NOT DONE. At this point I got really MAD! I was really late for work and it is unknown how long their stupid test can take. I yelled at them, yelled at the guy which told it will be ready at 3. Eventually, the manager showed up apologizing and offered Apple Care to compensate for inconvenience. 30 min later the test was over and they carried my computer to my car. So, I came at 3 and left at almost 5. 2 hours of my time was wasted.

BTW, the fan works fine now, no noise.
 
I got the same noise with my new Mac Pro (early 2009). I bought it some weeks ago, but use it for the first time two days ago. I heared the "humming noise" (?!) immediately (the noise is discussed for many times: https://forums.macrumors.com/threads/674185/, http://discussions.apple.com/thread.jspa?threadID=1971943). I took all the HDD off the case except my SSD-Boot Drive and still can here the noise, so it's no problem with HDDs. Today, I took it to my local Apple Service Provider, but they can't really hear the noise and had no idea what to do.

From earlier posts I learned, that some had success by adjusting the fans with smcFanControl; some exchanged their Macs with success; some exchanged their Macs three times without any change.

I'll try the smcFanControl hint tonight but remain unsure, if this is the solution, because my Mac is still under warranty (also still in the first 90 days) and should work as expected out of the box. So I may try, that they exchange my Mac, albeit I know, that might not work as stated above.
 
My 2009 Mac Pro sits on a wooden floor and i can hear the HDD humming quietly. The fans make hardly any noise.

I use SMC fan control when the temps start to climb and i found the intake and exhaust fans make the most noise. When i set them to run at 800rpm instead of the 600rpm default i really hear the difference. But the CPU fan (Booster) and PCI fan can be increased by 200rpm without much noise.
 
What do you guys think: is it save to start the Mac Pro without drives, graphics card and the side panel off? It's just in order to figure out from where the noise is coming. Or may I damage something?
 
What do you guys think: is it save to start the Mac Pro without drives, graphics card and the side panel off? It's just in order to figure out from where the noise is coming. Or may I damage something?
You'd be fine to do that (won't be open long enough to cake the fans and cooler surfaces up with dust). ;)
 
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