Thermals on M2 Max worse compared to M1 Max?

[TheRiddler1982]

Hi all,

I was using a M1 Max 10-core CPU 32-core GPU 32 GByte RAM 1 TByte model since its release back in 2021. As the RAM and storage have been my most limiting components (not performance!), I decided to upgrade to a refurbished M2 Max 12-core CPU 38-core GPU 96 GByte RAM 8 TByte model.

As I am doing a lot of panoramas with large RAW files it is such a game changer to have that amount of RAM. Further, I do not need to use external disks for adhoc work.

However, I was quite shocked on the temperatures and fan activities.

For instance, I could import RAW files in Lightroom Classic with my M1 model without fans going on and temperatures going above 70 degree Celsius (I have no longer access to that model, so I cannot provide you with a video). But doing the same with the M2 model, fans starts spinning up to arround 1.500rpm and temperatures hit 100 degrees Celsius. After importing, the fans stay active for 15 minutes even if the temperatures of the CPU cores are back to 50 degrees Celsius.

Is this normal behaviour? Can you confirm that? If so, I will return the M2 Max and try to get a maxed out M1 model.

It's like back with the Intel days, the Macbook gets hot on your legs, all the M1 spirit is lost with M2?

Is it any different with the M3 series?

Thanks for your help!

 

[leman]

M2 Max uses more power than M1 Max under heavy load, so higher temperature and fan activity are to be expected. I cannot comment on whether the figures you mention are within the normal range or not. M3 uses more power yet. In general, M1 Max CPU running at full power will consume around 45 W, M3 Max CPU around 60 watts. None of this is abnormal and works as expected.

In general, it’s perfectly fine for a modern chip to operate at 100C for prolonged periods of time and Apple has been designing their systems to take advantage of that for over a decade. Of silent operation is important for you, consider either the Air or the Pro series in the 16” chassis. It is also always possible to run your computer in low power mode.

 

[TheRiddler1982]

I am using the 16 inch model so because of the thermals I read before buying it. But this machine I got it constantly runs the fan. It's only 1.500rpm but this was not the case on the M1. The Air does not fit my needs. I was quite happy with the M1 Max in performance. I do not notice a gain in my use cases that much. So, I will return it and get a refurbished M1 Max with more RAM and storage. In my opinion, working with the M2 Max is like on the Intel. The body feels very warm even not under heavy load.

 

[Zest28]

M2 Max uses more power than M1 Max under heavy load, so higher temperature and fan activity are to be expected. I cannot comment on whether the figures you mention are within the normal range or not. M3 uses more power yet. In general, M1 Max CPU running at full power will consume around 45 W, M3 Max CPU around 60 watts. None of this is abnormal and works as expected.

In general, it’s perfectly fine for a modern chip to operate at 100C for prolonged periods of time and Apple has been designing their systems to take advantage of that for over a decade. Of silent operation is important for you, consider either the Air or the Pro series in the 16” chassis. It is also always possible to run your computer in low power mode.

I disagree. I noticed that Apple was using much more aggressive fan settings, as my 10nm Intel 2020 MBP was targetted to operate at 70 degrees, which is why the fans kick in much faster. Apple was not targeting 100C like with the M2 and M3 machines before.

Funny thing is, if you let the 10nm 2020 13" Intel MBP run as a hot as a M2 MacBook Air (allowing the temperatures to go to 100C), the fans of the 10nm 2020" MBP pretty much never kick in under "normal usage" at all, and it is basically as quiet like a M2 MacBook Air.

I'm personally not in favor or running these ARM Mac's at 100C, because if something breaks on these machines, you have to basically buy a whole new machine. So I would probably download software to control the fan settings and let it run cooler.

It's also one of the reasons why I'm sticking with my 16" M1 Max MacBook Pro as the M2 and M3 variants are just hotter overclocked versions of it. I did calculations of the clock frequency versus performance increase (corrected for the number of cores) a while ago, and the performance increase is mostly attributed to the higher clock frequencies (which comes with extra heat).

 

[leman]

I disagree. I noticed that Apple was using much more aggressive fan settings, as my 10nm Intel 2020 MBP was targetted to operate at 70 degrees, which is why the fans kick in much faster. Apple was not targeting 100C like with the M2 and M3 machines before.

I have never tested a 13” Intel model, but I did extensive testing on various 15” models (including the Intel 16” one). All Intel Macs I’ve tested since at least 2012 used temperature throttling strategy to control performance, with 100C as upper safe limit.

I'm personally not in favor or running these ARM Mac's at 100C, because if something breaks on these machines, you have to basically buy a whole new machine. So I would probably download software to control the fan settings and let it run cooler.

This doesn’t make any sense to me. Why would anything break if you run the chip at 100C?

It's also one of the reasons why I'm sticking with my 16" M1 Max MacBook Pro as the M2 and M3 variants are just hotter overclocked versions of it. I did calculations of the clock frequency versus performance increase (corrected for the number of cores) a while ago, and the performance increase is mostly attributed to the higher clock frequencies (which comes with extra heat).

Newer chips can operate at higher frequencies without using more power. M3 for example hits higher frequencies than M2 Max while using less power. M2 does use more power than M1, per core (and M2 Max uses even more power since it’s clocked higher).

Overall, it’s way too simplistic to characterize them as “just hotter overclocked versions”. There is a substantial amount of microarchitectural re-balancing between the Mx families to allow them to hit new performance and efficiency targets. And M3 is a new CPU core altogether.

 

[dmccloud]

I disagree. I noticed that Apple was using much more aggressive fan settings, as my 10nm Intel 2020 MBP was targetted to operate at 70 degrees, which is why the fans kick in much faster. Apple was not targeting 100C like with the M2 and M3 machines before.

Funny thing is, if you let the 10nm 2020 13" Intel MBP run as a hot as a M2 MacBook Air (allowing the temperatures to go to 100C), the fans of the 10nm 2020" MBP pretty much never kick in under "normal usage" at all, and it is basically as quiet like a M2 MacBook Air.

I'm personally not in favor or running these ARM Mac's at 100C, because if something breaks on these machines, you have to basically buy a whole new machine. So I would probably download software to control the fan settings and let it run cooler.

It's also one of the reasons why I'm sticking with my 16" M1 Max MacBook Pro as the M2 and M3 variants are just hotter overclocked versions of it. I did calculations of the clock frequency versus performance increase (corrected for the number of cores) a while ago, and the performance increase is mostly attributed to the higher clock frequencies (which comes with extra heat).

Most Intel and AMD systems have a max temp of 95C, at which point throttling and increased fan speeds take effect. Some mobile systems (laptops) actually have lower max temps due to the limited cooling options available in a small chassis. Depending on how a particular x86 system is configured, throttling may even happen sooner depending on how the fan curves and cooling profiles are set up.

Unlike x86 Processors (Intel and AMD alike), Apple Silicon can run at 100C for extended durations without significant degradation in either system longevity or performance hits due to throttling. Apple Silicon benefits from its custom architecture and consolidation of components onto the SoC, and is designed to handle higher temperatures without throttling. The loudest my 14" Pro with M2 Max has gotten was just loud enough to hear the air being forced out the vents, but even then there was no mechanical fan noise, just the sound of the air itself.

To call M2 and M3 "hotter overclocked versions" of M1 is a gross misstatement. There were changes made under the hood with both M2 and M3, including number of CPU and GPU cores, internal bandwidth, and ANE tweaks. When you add the switch to 3nm for M3 into the mix, calling it an overclocked M1 is beyond disingenuous.

 

[leman]

Most Intel and AMD systems have a max temp of 95C, at which point throttling and increased fan speeds take effect. Some mobile systems (laptops) actually have lower max temps due to the limited cooling options available in a small chassis. Depending on how a particular x86 system is configured, throttling may even happen sooner depending on how the fan curves and cooling profiles are set up.

Unlike x86 Processors (Intel and AMD alike), Apple Silicon can run at 100C for extended durations without significant degradation in either system longevity or performance hits due to throttling. Apple Silicon benefits from its custom architecture and consolidation of components onto the SoC, and is designed to handle higher temperatures without throttling. The loudest my 14" Pro with M2 Max has gotten was just loud enough to hear the air being forced out the vents, but even then there was no mechanical fan noise, just the sound of the air itself.

The max safe temperature for all modern x86 CPUs is around 100-105C, I don’t think there is any difference to Apples chips. It’s about the physical properties of the silicon after all.

 

[TheRiddler1982]

Newer chips can operate at higher frequencies without using more power. M3 for example hits higher frequencies than M2 Max while using less power. M2 does use more power than M1, per core (and M2 Max uses even more power since it’s clocked higher).

Having read through the forums, M3 Max fans even start much earlier now and have higher rpms. On the other side, I have seen a video from Max Tech showing that the M3 Max 16 inch body is cooler than M2 Max 16 inch body but temperatures go to 100 degrees Celsius, too. Further, the cooling system is of the same size as of M2 Max, thus smaller than M1 Max.

I sincerely hope to have the feeling of the M1 Max with M4 Max one day.

Or can somebody recommend a M3 Pro/Max Config which offers the same thermals als the M1 Max?

 

[JouniS]

The loudest my 14" Pro with M2 Max has gotten was just loud enough to hear the air being forced out the vents, but even then there was no mechanical fan noise, just the sound of the air itself.

My 16" MBP with M2 Max gets annoyingly loud when I play Baldur's Gate 3 and visit some of the more complex areas. Despite all the fancy tech, it's still a thin laptop that consumes ~100 W under full load. With that much heat, small fans operating in confined spaces are going to be noisy.

 

[theorist9]

The max safe temperature for all modern x86 CPUs is around 100-105C, I don’t think there is any difference to Apples chips. It’s about the physical properties of the silicon after all.

Some of the heat degradation concern is for associated components, like thermal paste, capacitors, plastics, etc. I'm sure the Apple engineers know what they are doing, and have done their best to take into account the thermal stability of all components in setting fan curves. Thus I agree with your position and wouldn't personally second-guess what they've done and concern myself with the temperatures. Plus I tend to keep AC+ on my machines, so if there's a problem it's on their dime rather than mine.

Having said that, it's worth noting that, even with the best engineering practices, they can still be mistaken in their predictions. I experienced such a mistake myself with my 2014 MPB, which twice needed to be repaired because the thermal paste wasn't sufficiently stable to handle the temperatures. It wasn't until they did the third repair, in 2019, that they got it right.

In summary, if I were sent back in time with a single MBP to help the allies win WWII more quickly, I'd tell them to keep it in a cool room to minimize the temps. Barring that, I'll just use the machine and not worry about it.

 

[nathansz]

Unlike x86 Processors (Intel and AMD alike), Apple Silicon can run at 100C for extended durations without significant degradation in either system longevity or performance hits due to throttling. Apple Silicon benefits from its custom architecture and consolidation of components onto the SoC, and is designed to handle higher temperatures without throttling.

Intel cpus are also fine to run at 100 degrees. Nothing magic about apple silicon there.