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Has anyone else noticed the power supplies in the Max Tech Mac Studio teardown (an M1 Ultra) and the iFixit Mac Studio teardown (a M1 Max) are different? According to the Apple Spec page the electrical specs of both models are the same (370W).

So are the power supplies different because one is a M1 Ultra and the other is a M1 Max even though they have the same total wattage specs? Or are they meant to use the same power supply board and there was a design change to the power supply board late in preproduction, and some of both models were built with an older version of the power supply board? It's pure speculation, but if so, that could possibly explain why some units have the high-pitched whine and others don't have it at all.

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LTT just did a video on the Mac Studio and theirs (both Max) have a different PSU. Maybe one of them is causing the coil whine.

 
I am following this thread with great interest - I do not own the Mac Studio, nor have I ordered one. I am just a prospect buyer to replace a Mac mini if/when needed. My observations are that the Mac Studio cooling architecture and fan profile has not been engineered properly, there is a lot to be desired. Of corse it is a small enclosure, but there is so much more that can be done within those small boundaries:

1. There is no need for such a cool and power efficient chip to be cooled all the time at this high 1300 RPM.
2. Even when used at 100% the fans stay the same RPM and the chip is at 65°C or lower.
3. If the power supply needs cooling (which I doubt at the minimal power consumption of the chip and its efficiency) - then why is the power supply at the bottom and not at the top of the enclosure so that its hot air is exhausted immediately not to affect other system components? Why not have a separate air tunnel for the power supply alone, like dedicate one of the fans to it?
4. Two small turbine fans will make more noise than one large turbine fan with proper air channels at lower RPM. Why two fans were needed?
5. The perforation holes of the chassis may be too small. I can see why this may be intentional at the bottom to collect dust particles (acting as a filter), but at the rear, those are clearly too small and may create unnecessary pressure in the enclosure. Has anyone counted the perforated wholes on the bottom and at the rear to see if they are equal number (for equal in-out air flow without causing pressure)? The Mac mini has just one large exhaust hole in the back for air to come out.
6. Even the geometry of the perforation holes can create noise, they are just round with sharp edges. Usually to minimize noise, honey-cone perforation is used to avoid and break turbulence etc. Like in the Mac Pro that whole "cheese-grater" thing.
7. From the tear down-videos, I did not really see any guided air-channeling for cooling. The power supply and the "logic board" are just layered on top of each other, and there are no separate guides to channel the air for individual cooling. The chip is cooled by heat pipes and heat sink, but the air sucked through it is already heated by the power supply.
Amazing, have you applied for a job at Apple yet? They surely could use your expertise, as they don’t know how to design a computer, obviously :rolleyes:

Honestly, what is wrong with people nowadays? ?
 
Yes, they sure do know... else we wouldn't have this 32 page thread would we?
OK, coil whine is unacceptable, no argument here.

But as for fans running all the time, that’s how it was designed to work (as a mini workstation) and that’s it.

Now for some people that amount of constant fan noise is unbearable, please sell the Studio/return it/don’t buy it/buy mini or Air or MB Pro. Problem solved.

Or show me an equivalent PC/Mac desktop with equal computing power which makes LESS fan noise…
 
OK, coil whine is unacceptable, no argument here.

But as for fans running all the time, that’s how it was designed to work (as a mini workstation) and that’s it.

Now for some people that amount of constant fan noise is unbearable, please sell the Studio/return it/don’t buy it/buy mini or Air or MB Pro. Problem solved.

Or show me an equivalent PC/Mac desktop with equal computing power which makes LESS fan noise…
A mini workstation can be silent at idle and low load, and then gradually ramp up when temperatures rise demands it. There is nothing that can excuse the need for silent computing. Even my MP6,1 which has a higher TDP, is silent at idle and low load. What Apple designed does not seem to appeal to a lot of people, me including. It appeals to others that don't mind the noise - great! At the end, people will vote with their wallet.

Edit: A mini workstations that sits on your desk 1 meter or less away from your ears should be silent. A tower workstation that sits below your desk can be a little noisier, the distance will drown some of the noise.
 
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A mini workstation can be silent at idle and low load, and then gradually ramp up when temperatures rise demands it. There is nothing that can excuse the need for silent computing. Even my MP6,1 which has a higher TDP, is silent at idle and low load. What Apple designed does not seem to appeal to a lot of people, me including. It appeals to others that don't mind the noise - great! At the end, people will vote with their wallet.
In other thread (the poll), the majority of people voted that the Studio is quiet or that they do not mind the noise.

As for voting with one’s wallet - exactly my point. Don’t like it - do not buy it. I’m glad that we are in agreement here.
 
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Got mine 2 days ago and no complaints.
Yes, I can hear fan noise if i put my ear close to it.
But my Windows PC way louder even at idle which is less CPU performance.
 
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LTT just did a video on the Mac Studio and theirs (both Max) have a different PSU. Maybe one of them is causing the coil whine.


I discovered that there were 2 different power supplies from previous teardowns of a Max and an Ultra, and posted those pictures a few days ago. I guessed that might be why some Studio's have the whine and others don't, but that would require that both power supplies were used in both models. This is the first confirmation that is true. So yeah, that makes it even more suspicious that one power supply has whine and other doesn't. I guess we will have to wait for people to start tearing down Studio's known to have whine to see which power supply, or supplies, they have.
 
But as for fans running all the time, that’s how it was designed to work
You say that with such certainty, one could almost believe you actually know that's a fact. The only problem is: You actually don't.

There is *obviously* something going on here. The weird thermal envelope (the fans almost never spin up, even under heavy load, the CPU temp stays much lower than in the Macbook Pro as if performance was artificially throttled, the coil whine, etc.). Given all these circumstances, coming out here and stating "that's how it was designed. period." is pretty ****ing bold.
 
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A mini workstation can be silent at idle and low load, and then gradually ramp up when temperatures rise demands it. There is nothing that can excuse the need for silent computing. Even my MP6,1 which has a higher TDP, is silent at idle and low load. What Apple designed does not seem to appeal to a lot of people, me including. It appeals to others that don't mind the noise - great! At the end, people will vote with their wallet.

Edit: A mini workstations that sits on your desk 1 meter or less away from your ears should be silent. A tower workstation that sits below your desk can be a little noisier, the distance will drown some of the noise.
Mine is on my desk and is silent, don't hear a thing. At idle or low loads I can put my ear right next to my Studio Ultra vents and I don't hear a thing, when I stress it a bit using RX with my standard suite of modules and if I put my ear next to the vents, I can hear a bit of a whooshing sound, but with my head back in my normal position, still don't hear a thing.

There are two things going on, the fan noise which I believe is normal and for most people not a factor and the high pitched whining noise which I don't believe is normal and is caused by a defect of some kind. Mine certainly has some fan noise though for the most part I can't hear it unless I am really stressing my Mac and the ambient noise is very low, if under normal circumstances with some background noise I can't hear the fans at all. I have yet to hear any high- pitched noises at all, none under any circumstances. I believe the majority of Mac Studio users experiences are the same as mine, and the folks that are having issues with the whining sound are a minority of users that have received defective Macs, which may why the shipping dates have slipped, it could be Apple is working on the problem.
 
They surely could use your expertise, as they don’t know how to design a computer, obviously :rolleyes:

Honestly, what is wrong with people nowadays? ?
Well, Apple didn't do it right this time for whatever reason. Nothing about the cooling system makes much sense, and I sure hope firmware can fix some of it.

As for the coil whine, mine doesn't have that.
 
Or show me an equivalent PC/Mac desktop with equal computing power which makes LESS fan noise…
At idle, my i9 (Lenovo SFF 340 I think) is quieter than my Studio Mac. I can't hear the PC until it gets work going, but I can hear my Studio. When the PC is really working is about the only time I can't hear my Studio. :)

Bigger slow moving fans are pretty quiet.
 
You say that with such certainty, one could almost believe you actually know that's a fact. The only problem is: You actually don't.

There is *obviously* something going on here. The weird thermal envelope (the fans almost never spin up, even under heavy load, the CPU temp stays much lower than in the Macbook Pro as if performance was artificially throttled, the coil whine, etc.). Given all these circumstances, coming out here and stating "that's how it was designed. period." is pretty ****ing bold.
I would trust myself to be just as ****ing bold. But of course no one can be sure. But I had an Ultra and a Max Mac Studio. Both sounded exactly the same. I didn't have the coil whine. But the fan noise bothered me. Definitely the loudest computer I had (during idle) since 2006.

But looking at Apples Technical Specification the 25 dB are definitely as designed and with a little bit grain of salt coming from the manufacturer itself these data is actually not far off the 30-35 dB I measured 10 cm behind the vents during idle.

Also it is possible to get the fans spinning faster than 1300 rpm by taxing the GPU and CPU at the same time. Just by playing StarCraft II for example.

I suppose(!) Apple designed this for professionals for whom it might be more pleasant to have an almost silent system 99% of the time instead of a silent system that spins the fans up and down every time they do actual work. And I think that might be the right guess by Apple for the target group.
As a semi-professional who does everything with its computer and spends most of the time doing easy stuff any iPad could handle I would of course prefer Apple would have optimized for silent as long as possible. I wouldn't mind the occasional fan uproar when I do actual work. But if you do that all the time everyday it might get annoying.
 
I suppose(!) Apple designed this for professionals for whom it might be more pleasant to have an almost silent system 99% of the time instead of a silent system that spins the fans up and down every time they do actual work. And I think that might be the right guess by Apple for the target group.

I still don't get this argument. We know that at 1300 RPM the system stays below 70℃ under load. Why not meet in the middle and have a truly silent system under light load and "spin up" the fans to the already deemed acceptable 1300 RPM under load. Then your range is silent to almost silent rather than always almost silent. It's not like the alternative is 0 or 2500 RPM.

I'm still not being convinced that "constant fans" was a design objective.

Edited for typos
 
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OK, coil whine is unacceptable, no argument here.

But as for fans running all the time, that’s how it was designed to work (as a mini workstation) and that’s it.

Now for some people that amount of constant fan noise is unbearable, please sell the Studio/return it/don’t buy it/buy mini or Air or MB Pro. Problem solved.

Or show me an equivalent PC/Mac desktop with equal computing power which makes LESS fan noise…

Unfortunately it's not just "constant fan noise". It's fans that whine for some and have annoying overtones for others. I've certainly had computers with fans that were less annoying, including other computers made by Apple. People have every right to complain about products.
 
I discovered that there were 2 different power supplies from previous teardowns of a Max and an Ultra, and posted those pictures a few days ago. I guessed that might be why some Studio's have the whine and others don't, but that would require that both power supplies were used in both models. This is the first confirmation that is true. So yeah, that makes it even more suspicious that one power supply has whine and other doesn't. I guess we will have to wait for people to start tearing down Studio's known to have whine to see which power supply, or supplies, they have.
Everyone including me would assume there must have been different power requirements in Max vs Ultra that they would've needed different PSU, despite both rated at 370W.

Linus' video accidentally proved otherwise by ordering the same SKU in different time frame to get the two PSU, and the first thing he did was to swap them and it worked. Then from the iFixit teardown we saw clearly the fine print on one of the PSU says "Rev. B".

Coupled with the fact that we have people returning their first Studio with noise issue, got a 2nd unit and reported to not hear anything close to the 1st one. So yes we can pretty much assume if not confirm that there are noise issues exclusive in one PSU and it is a lottery which one you get, or at least initial orders had that problematic PSU.
 
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The studio itself is a great product.
It bridges the gap between the mini and the pro, when it comes to desktop use.
Sure, there was the iMac pro previously, but I personally dislike the iMac Package.
The Studio was my dream Mac. Compact, powerful, variety of ports. I had never been so sad to return a product.


Everyone including me would assume there must have been different power requirements in Max vs Ultra that they would've needed different PSU, despite both rated at 370W.

Linus' video accidentally proved otherwise by ordering the same SKU in different time frame to get the two PSU, and the first thing he did was to swap them and it worked. Then from the iFixit teardown we saw clearly the fine print on one of the PSU says "Rev. B".

Coupled with the fact that we have people returning their first Studio with noise issue, got a 2nd unit and reported to not hear anything close to the 1st one. So yes we can pretty much assume if not confirm that there are noise issues exclusive in one PSU and it is a lottery which one you get, or at least initial orders had that problematic PSU.
I’m not sure about that in its entirety. My unit was clearly being driven by the fans and not the power unit. I could hear the wind when the fan spun up and it changed with intensity when I adjusted the rpm. When I put the system to sleep and the fans stopped spinning the sound went away entirely
 
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I’m not sure about that in its entirety. My unit was clearly being driven by the fans and not the power unit. I could hear the wind when the fan spun up and it changed with intensity when I adjusted the rpm. When I put the system to sleep and the fans stopped spinning the sound went away entirely
Right, I was totally going on a tangent there.

End of the day it will take some electrician doing directly wired metering tests to these PSU's to make any conclusion, because it will isolate the PSU if coil whine is present on this or if what people like you hear is only air moving sounds.

But I personally don't think these really should matter, we are not on a PC builder forum but in Macrumors. The Mac Studio is supposed to be a buy-and-forget computer, if it gives you unbearable noise it doesn't matter why it happens, it is all or nothing.

However if it is fixible or if the problem is only present in a certain shipment, then as a buyer we could know more to avoid this issue since Apple of course wouldn't disclose anything related to this.
 
You say that with such certainty, one could almost believe you actually know that's a fact. The only problem is: You actually don't.

There is *obviously* something going on here. The weird thermal envelope (the fans almost never spin up, even under heavy load, the CPU temp stays much lower than in the Macbook Pro as if performance was artificially throttled, the coil whine, etc.). Given all these circumstances, coming out here and stating "that's how it was designed. period." is pretty ****ing bold.
Maybe the fact that both Mac Pro 2013 and Mac Pro 2019 have fans going on all the time (they may be quieter at idle, though) should give you the hint about my boldness ;)

Unlike many here, I can draw conclusions based on how Apple designed their previous workstations. Also, the cooling system (my guess) is over-engineered to allow for future processor models to use the same case/innards.

As Apple themselves admitted, 2013 Mac Pro couldn’t have had processor/GPU upgrades, because the thermal envelope was too rigid. They didn’t make the same mistake with the Studio…
 
At idle, my i9 (Lenovo SFF 340 I think) is quieter than my Studio Mac. I can't hear the PC until it gets work going, but I can hear my Studio. When the PC is really working is about the only time I can't hear my Studio. :)

Bigger slow moving fans are pretty quiet.
I understand.

The thing is that for me, idle is maybe 20 mins to check emails and such. Then the work starts and with heavy sessions in Logic Pro X with plenty of virtual instruments, the fan in my mini 2018 starts ramping up, it goes down, then up again and so on. I (and many other music producers) hate that loud bursts of noise. I’d rather have the workstation which is consistently nearly quiet (like 2013 or 2019 Mac Pro, or indeed Mac Studio) than the system with fans doing rollercoaster ride of ramping up and down all the time.

If one is using Studio for office stuff and browsing the internet then I understand the desire for it to be 100% quiet, but in such cases M1 mini would suffice, IMHO.

I have iPad Pro 13” for browsing internet and media consumption, my studio computer is for work.
 
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