Mid-2010 Mac Pro HUMMING NOISE

[namethisfile]

Hey,

So, are Hums from these Mac Pro's normal? I'm asking because I haven't been able to find a definitive consensus from the net.

My Mac Pro, which I got used from an eBay reseller has a hum. I've since put books on top of the Mac Pro and that has somewhat mitigated the hum to a low and more tolerable level. It's not fan noise or HDD noise. I've since cleaned and dusted the Mac Pro. And, the hum is still there.

Is this a defect, a dying component or is the HUM just a normal occurrence with Mac Pro's since they're all aluminum with little vibration reinforcements that they hum like this?

Thanks!

PS--the HUM sounds like a Yoga Instructor meditating and humming. It's a constant HUMMMMMMM... if you know what I mean....

PSS--My Mac Pro is 5,1, mid-2010, 6-core CPU, etc. The tower one.

 

[bjar]

Check optical drive. That was my issue. Even without a cd it would hum the entire time. I could open the door on the case and push a little on the drive tray and it would stop.

 

[namethisfile]

Check optical drive. That was my issue. Even without a cd it would hum the entire time. I could open the door on the case and push a little on the drive tray and it would stop.

Huh! It could be my mind playing trix on me. But, the Mac Pro hum is a little quieter.

I, actually, replaced the Apple optical drive that was in there, with an optical drive I had laying around that was in my former PC case. I did that because the Apple optical drive had something inside that was making a rattling noise, anyway. And, my other optical drive did not have any rattling noise.

The hum is still there but, subtly, less. I'm not sure if it was the optical drive switch. Or, that it is my ears playing hearing games.

The only thing odd is that the DVD drive icon says TSSCORP something instead of what it used to say with the Apple optical drive in there.

Also, one more thing, this TSSCORP optical drive is also quieter than the Apple one. But, I didn't really minded that before. The issue was that the whole thing have this hum.

Anyway, I don't know.

 

[steveOooo]

Mine has been humming since I got it in 2011.

 

[carpsafari]

I'm pretty sure its the GPU you hear!
Can be annoying.

 

[steveOooo]

Ati 5770 - ok
Amd 7950 - more noise (more power)
Amd r9380 - less noisey - about the same as the 5770, maybe a bit quieter

cpu upgrade from 2.8 quad core to 6core 5690 3.4ghz resulted in a bit more noise

 

[namethisfile]

I'm pretty sure its the GPU you hear!
Can be annoying.

It's not. I have the Gigabyte RX460 in there and the fans don't even spin, until, it's stressed.

My guess is that the machined all aluminum construction with hardly any vibration insulation materials is causing the hum.

I have the Mac Pro under my desk where I hear the hum more easily. It's less now that I switched optical drives and that I have books on top of it. But, it's still there. When I duck my head near the Mac Pro, I don't hear the hum. But, the fans.

It's hard to describe. I'm leaning to case vibration causing the hum because of its omni-present nature. It's hard to pinpoint it, even when I have paper folded into a cone-shape as a hearing aid to find the source of the hum.

Also, the fact that putting weight on top of my Mac Pro lessens the hum, is another evidence pointing to some vibration issue.

Anyone else wanna chime in? Pun intended....

 

[pastrychef]

since they're all aluminum with little vibration reinforcements that they hum like this?

If the case or lack of "vibration reinforcements" were the problem, it would have been all over the internet years ago.

 

[h9826790]

It's important to identify the source, otherwise, hard to decide the solution.

There are few possible sources. Basically you have to open the side panel when it happening, and give a little push to:

1) each HDD tray
2) PSU
3) optical drive cage
4) PCIe fan
5) PCIe card (e.g. GPU)
6) Processor cage

If the noise change clearly when you push that item, then you know that should be the source, and then we can decide how to fix it.

e.g. there was a member here identify that the noice was actually from the processor cage. So, he just put a piece of paper between the cage and the case, since then, the noise stopped.

 

[mattspace]

my 2009 dual used to get a vibration noise that went away with even the most gentle touch to the pci slot covers on the back. seems to have gone away since the machine was hung from its top handles.

 

[namethisfile]

Well, I did the "touching" of parts in my Mac Pro as some of you have suggested and I can't get the sound to change.

It could be the rear fan creating the vibration and humming. Maybe, when I have some time, I will look into it further and disassemble it or something.

EDIT: It's not the rear fan.

At this point, I think, I'll just put weight, aka books, on top of my Mac Pro as a permanent solution. It does mitigate the hum.

 

[hfg]

It could be a out-of-balance fan or a bad fan bearing which causes the chassis to vibrate. You say it stops if you put books on it (dampen it) which would indicate vibration.

It could also be a failing hard disk bearing, which would eventually emit a loud screeching noise, and you could test that by removing the drives to see if the noise goes away, then replace them one at a time until it comes back.


I have a SSD only iMac with an external 4-disk enclosure which makes the antique desk it is sitting on hum occasionally. It will usually go away if I open/close the pen drawer, or slightly move the disk enclosure. Again ... vibration making the desk hum.

My 2012 cMacPro makes no discernible noise, humming or otherwise ... although I do hear the video card fan rev up occasionally.

 

[namethisfile]

It could be a out-of-balance fan or a bad fan bearing which causes the chassis to vibrate. You say it stops if you put books on it (dampen it) which would indicate vibration.

It could also be a failing hard disk bearing, which would eventually emit a loud screeching noise, and you could test that by removing the drives to see if the noise goes away, then replace them one at a time until it comes back.


I have a SSD only iMac with an external 4-disk enclosure which makes the antique desk it is sitting on hum occasionally. It will usually go away if I open/close the pen drawer, or slightly move the disk enclosure. Again ... vibration making the desk hum.

My 2012 cMacPro makes no discernible noise, humming or otherwise ... although I do hear the video card fan rev up occasionally.

Yeah. I'm leaning to an out-of-balance fan, too. I just don't know which one. I will have to investigate it further and look at some "How to..." videos on Youtube, or something. Lol!

I can rule out failing or noisy HDD. I got this cMP used from eBay and the 1TB Hitachi Deskstar HDD that they gave me was noisy as hell. It has a "MAR 2008" sticker on it, so it's not the stock HDD and is even older than the cMP they sold me (a Mid-2010). No big deal. I had two newer Barracuda drives in hand, anyway, which are a lot quieter and of which I am using for storage. I also have two SSD's in there for the OS/Apps and a "scratchdrive."

The other thing I am going to do, is see if getting the Mac Pro off the carpet will make a difference by putting it on a slab of wood from a shelf or something. The Mac Pro is a bit tipsy sitting on the carpet. Not sure if that will make a difference.

But, thanks for the input!

 

[hajwer]

Maybe a bit old that thread, but I am handling with the same problem as this thread is about.

I got a 4.1 and have the same very deep humming from the entire machine. I stopped all fans, touched all parts and pulled out all drives. But humming did not got away.

But I may have found a solution. The humming is created by the front and rear fan of the processor cage. At idle they run both at 600rpm which leeds to conflicting vibrations, delegating to the entire case.

I can easily test this by setting these both fans to a high drive and then back to auto (eg with Macs Fan Control). You should hear the raising humm with falling rpm, finding it‘s maximum a few seconds after both fans settled back to 600.

So I played around with Macs Fan Control and my solution is:
Leave the exhaust at auto and set the intake to custom at 720rpm. For me this lets the humming disappear.

But I have no idea yet, what impact this would have on the thermal situation under load. Considering Apple is leaving the fans very long on idle and there are three other fans in the processor cage, I think it’s not a huge impact.

 

[h9826790]

I have roughly the same intake and exhaust fan setting to avoid that beat frequency. It works very well.

Anyway, I suggest you use SMCFanControl but not MacsFanControl for this kind of fan control.

SMCFanControl increase the intake fan speed by altering the minimum RPM. It tell the SMC that the intake fan minimum RPM is now 700, therefore, the fan will spin up to 700 (if it's below 700). And if your CPU is really running hot, the SMC call ask the fan to spin up further, because the minimum fan speed won't stop the fan to spin faster.

However, MacsFanControl is controlling the fan by assigning a target RPM. It tell the SMC that the intake fan target RPM is now 700, therefore, the fan will spin up (or down) to 700 RPM. If your CPU is overheating, the intake fan will still only spin at 700, because that's the target RPM. It override all other parameter.

 

[hajwer]

Thanks for the advice! I was looking for a way to alter only minimum drive. I tried smcFanControl earlier but it didn’t work. Moved it to the applications folder -> working!

But what’s that Prefpane you are using? This does not look like smcFanControl.

 

[h9826790]

Thanks for the advice! I was looking for a way to alter only minimum drive. I tried smcFanControl earlier but it didn’t work. Moved it to the applications folder -> working!

But what’s that Prefpane you are using? This does not look like smcFanControl.

It's an open source Fan Control software, I modify it to fit my own usage. I never post the one that I am now using, because it require assistant from smcfancontrol. A bit too complicated on the initial setup, so I keep it for myself. But there is a thread in this forum for this particular software, and there are few other versions available at there.

https://forums.macrumors.com/thread...ol-now-version-2.1340705/page-6#post-24547028

What I want is both PSU and PCie fans are controlled by setting target RPM. Because there is a SMC bug in the 2009 mode which may cause high PCIe and PSU fan until stress the GPU after each boot. This is annoying, and cannot be fixed by altering the minimum fan speed.

On the other hand, I want all other fans are controlled by only altering the minimum fan speed, so that I don't need to worry about CPU overheat.

Besides, I want to control BOTH the minimum fan speed, AND the spin up temperature threshold.

Furthermore, I want the CPU Booster fan will spin up automatically if the Northbridge is getting warm. (this single fan will spin up either the CPU or Northbridge temperature reach the threshold)

Last but not least, I want to minimise the CPU usage (MacsFanControl actually use about 10x more CPU than this software. Even though we are just talking about 3-5% CPU usage, but I personally don't like it)

Since there is no software can fulfil all these requirement. So I decided to modify one for myself.