PSU & Fan Sounds on 2012 Mac Pro 5,1

[Nanco]

Hi there,

I wondered if someone could help to clarify if the sounds in the following video were normal or a sign of something wrong:

PSU Fan Hum and PSU Buzz.mp4 - Google Drive

The PSU is making a fizzing sound up close. The fan is also emitting a low whirring sound that is quite noticeable from a distance, even when the side is on the case. I also own a 2008 Mac Pro (3,1?) and can confirm that the PSU is virtually silent in comparison.

Any help will be appreciated.

Many thanks!

 

[pm-r]

The fan is also emitting a low whirring sound that is quite noticeable from a distance, even when the side is on the case.

It was my understanding that it was very bad practice to run those Mac models without the side panel in place.

I believe doing so could mess up the cooling air flow and it could overheat.

If the noises are annoying you, I could barely hear them in your audio, then put some pieces of sound absorbing board or material around the Mac Pro, but leave some air slots open for cooling. Or wear some good sealing earphones.


- Patrick
======

 

[Nanco]

It was my understanding that it was very bad practice to run those Mac models without the side panel in place.

I believe doing so could mess up the cooling air flow and it could overheat.

If the noises are annoying you, I could barely hear them in your audio, then put some pieces of sound absorbing board or material around the Mac Pro, but leave some air slots open for cooling. Or wear some good sealing earphones.


- Patrick
======

It was a bit tricky to get a video of inside the case without removing the side first. There's no other way I could get to the PSU fan otherwise. ;D

The Mac is usually situated under my desk which drowns out a lot of this noise anyway, but thats not my concern. I’m really just curious whether the PSU and fan should be making those sounds in the first place. I've been doing a lot of troubleshooting lately (see my other thread) so I really just want to make sure that I'm covering my grounds and that there aren't any underlying problems with my Mac.

I’d recommend listening to the video using headphones as the sounds aren't as obvious if you are listening through smaller speakers or at lower volumes.

 

[pm-r]

I’m really just curious whether the PSU and fan should be making those sounds in the first place. I've been doing a lot of troubleshooting lately (see my other thread) so I really just want to make sure that I'm covering my grounds and that there aren't any underlying problems with my Mac.

Well, even if it isn't quite normal, what were you planning to do about it???

Why not just carry on and get some work done with it and enjoy it as it is. Life's too short, but maybe you are too young for that to have become a reality.

Even machines seem to have some sort of personality, so just live with yours until it quits. Then you can really deal with it, as that's when it will no doubt be a bit more of a problem at that point.



- Patrick
======

 

[Nanco]

Well, even if it isn't quite normal, what were you planning to do about it???

I cannot do anything about it until I have clarity from someone who knows what they’re talking about. A potentially faulty power supply isn’t something I want to second guess a solution to if I don’t have the answer myself otherwise I wouldn’t have made this thread. I’m sure you can appreciate that.

Why not just carry on and get some work done with it and enjoy it as it is. Life's too short, but maybe you are too young for that to have become a reality.

I know I said that any help would be appreciated, but I didn’t create this thread to be patronised. Stick to the topic please.

Even machines seem to have some sort of personality, so just live with yours until it quits. Then you can really deal with it, as that's when it will no doubt be a bit more of a problem at that point.

No disrespect Patrick, but unless you can actually confirm whether those sounds in my video are regular or not, we’ll just end up going around in circles and getting nowhere. If you can’t hear them to begin with, then maybe you aren’t the best person to help me with this problem.

Can someone with a better ear offer any clarity on whether these sounds indicate a potential problem or if its completely normal for the PSU and fan to be this noisy?

 

[pm-r]

Can someone with a better ear offer any clarity on whether these sounds indicate a potential problem or if its completely normal for the PSU and fan to be this noisy?

That would be interesting to read any such answers. There should be a decent number of 2012 Mac Pro 5,1 users among the members.

I guess things might have been different if you had ended up with one of the older, 2000 era Power Mac G4 when a limited range of serial numbers of that model was noted for a noisy fan, earning them the unofficial designation "Windtunnel" G4 Macs. And there was no question at all of the noise they produced, they really howled!!!

If you want, you could always just change your existing ones for quieter fans etc. as is shown in post #25 at:
Mac Pro 5.1 Replace Fans | MacRumors Forums



- Patrick
======

 

[jasongoldworthy]

hi there,


I have just listened to the video with my headphones on and the fizz/buzz isn't normal one way to tell if its the fan is to temporarily stop the PSU fan with your finger obviously it will ramp up when you let it go.


but will then settle down,


noises from the PSU are never good in any form as mine is silent as a baby sleeping.

 

[iggibar]

Fan noise
You mentioned in the previous thread that you tried cleaning the mac pro with compressed air. Problem with compressed air is that you can't control the trajectory of the dust that you are freeing, and it's super easy for it to get crammed underneath fans and other components. Not saying that this happened, but it just stood out to me and thought I would mention it. I've used CA only ONCE in my life to clean, and it was never on a computer.

With that said, bearings on PC fans have certain lifespans. I have 3 Mac Pros. My 4.1 is dust free inside, but the largest fan has a loud bearing. I thought about replacing it, but I've never had any performance issues, and the slight noise is not a problem for the low usage I get out of it.

I try to do the best when it comes to maintaining my computers, and with my Mac Pros, I noticed something interesting with their fans. They have floating bearing designs(same as the MacBook Pros) as apposed to bearings that are sandwiched between two roller sides. These are pretty reliable and smooth, but they are VERY EASILY put off balance with dust buildup, or worse, if you clean one area and forget another area(like the back that might be harder to get to). I noticed this issue when I was cleaning the front fan on my Mac Pro 5.1. I cleaned the front of the fan blades, but wasn't able to get 100% of the back of the blades. There was a humming noise that the fan started making as soon as I turned it on. It stumped me until I cleaned them 100%. The humming noise is caused off-balance blades being forced into balanced rotation by the rigid fan mounts to the frame. You can test this by putting a tiny piece of tape on a blade to put it out of balance.

As for the comment you posted previously about opening the POWER SUPPLY, please don't do that. The amount of stored energy in those capacitors can EASILY kill you if it's not discharged, and they DON'T discharge for a REALLY LONG time! Please be careful with that!!

Clicking noise
Regarding the clicking noise you had issues with, since I haven't heard it, and knowing you said it wasn't HDD related, I'm going to go with something that I've had concerns a while ago with my Mac Pros. It's a common concern with tower Mac Pros and Power Macs. If you have inconsistent/fluctuating power in an area of your house(common in apartments or old houses), your relay will switch to try and maintain constant power within your power supply to the best of its abilities. When the relay switches, it makes a clicking noise. It's just slightly less noisier than a clicking pen on my Mac Pro 4.1/5.1. Surge protectors do not help in this situation. Mac Pros have always had the lowest amount of total power supply rating they could get away with. Using a dual card setup easily puts it at its max rating once you start maxing out on HDDs/RAM/other connections. The best way to test this is to plug in a good battery backup system with surge protector(almost all of them have built-in automatic voltage regulation). My home office has a lot of electronics and devices that are on 80% of the time. I use three CyberPower 1325va Sine Waves to maintain constant power to my computers and NAS. Every now and then, one of Sine Waves will alert me and chime to let me know there is inconsistent voltage, and will maintain constant voltage by running off the battery until incoming power is stabilized. A normal surge protector will NOT help you in this situation. Everything in this room used to be cool until I decided I wanted a 2.0cf mini cooler for my drinks in it. This thing sucks the power out of this room like a vampire LOL.


The cheapest way to test this is to move the Mac Pro to an area of the house where you know there isn't a lot of power being drawn.