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crazy dave

macrumors 65816
Sep 9, 2010
1,453
1,226
I had no idea that there were so many people who are so passionate about running their CPUs at 100 C all day, every day. This has been a very enlightening conversation. ?
They're combating the idea that running your CPU at 100C is dangerous to either the CPU or other computer components because it isn't. You are free to do with your own computer as you wish. If it makes you feel better to have your fans kick sooner and harder than Apple intended, go for it. Of course the most likely component to fail then would be your fans - moving parts and all that.

A fundamental misunderstanding that you and some of the others arguing the same position as yours have in this thread is the distinction between heat and temperature. Degrees C is a measure of temperature and is related to but not the same as joules or watts - the energy or energy per sec. When discussing how *heat* damages outlying components the latter two measurements are far more important than the first one. This is one reason why a CPU's watts and perf/watt *matter* when discussing cooling. When discussing say dangerous skin temperatures we know how much energy is dissipated on contact to skin from polymer and metal surfaces and what temperatures are safe and which are not. But even so what really matters is the energy released on to your skin, both total and instantaneously. Consider a small needle burning your skin at 100 degrees celsius vs a massive vat of boiling water (also 100 degrees C) being dropped on you. They may be at the same temperature, but there is a considerably worse outcome for the latter even if the former isn't pleasant. A cooling system is rated to dissipate *watts*, not *degrees C*, in order to keep the user and the rest of the computer comfortable.
 

TimmuJapan

macrumors 6502
Jul 7, 2020
373
651
Survey:
Which situation do you think your computer has the best chance of a long life,

A) the cpu and surrounding components are constantly blazing hot, close to 100C. This situation persists often for a weeks at a time, hours upon hours, days after days, weeks on end. It will constantly run blazing hot, close to 100 C.

B) the cpu and surrounding components are generally at 30~40 C. The temperature comes up for heavy loads. Fan curves are adjusted to keep the temperature down. Thermal paste is re-applied after some years to improve thermal performance.

C) there will not be a difference between A) and B) in affecting the lifespan of the product.

I think that based on what intel wrote on their website, The safer choice is B.
last sentence from the link below,
"....PC cooling isn’t just good practice. It’s also important for getting the best performance from your build, and for potentially increasing the lifespan of your components."

https://www.intel.com/content/www/u...g-the-importance-of-keeping-your-pc-cool.html

There is a potential that helping to keep your system cool will help it last longer. Not a certainty, but a potential. I think that as a company, Apple would like all of us to replace our devices every 2-4 years, and even with apple silicon, a quieter device also equals a hotter device, which potentially may not last as long as a cooler device. Less devices dying after 3 years = less money for apple, so it is in their interest financially for their engineers to also consider planned obsolescence and ways to make consumers buy something new again. They are a company. They are not a not-for-profit scientific research institute. It s not in their financial interest to design devices made to last 10-15 years, but lucky for us, sometimes they do last that long, and they may last longer if we try to keep them running cool. potentially. I’ll air on the side of caution.
 
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crazy dave

macrumors 65816
Sep 9, 2010
1,453
1,226
Survey:
Which situation do you think your computer has the best chance of a long life,

A) the cpu and surrounding components are constantly blazing hot, close to 100C. This situation persists often for a weeks at a time, hours upon hours, days after days, weeks on end. It will d constantly blazing hot, close to 100 C.

B) the cpu and surrounding components are generally at 30~40 C. The temperature comes up for heavy loads. Fan curves are adjusted to keep the temperature down. Thermal paste is re-applied after some years to improve thermal performance.

C) there will not be a difference between A) and B) in affecting the lifespan of the product.

I think that based on what intel wrote on their website, The safer choice is B.
last sentence from the link below,
"....PC cooling isn’t just good practice. It’s also important for getting the best performance from your build, and for potentially increasing the lifespan of your components."

https://www.intel.com/content/www/u...g-the-importance-of-keeping-your-pc-cool.html

There is a potential that helping to keep your system cool will help it last longer. Not a certainty, but a potential. I think that as a company, Apple would like all of us to replace our devices every 2-4 years, and even with apple silicon, a quieter device also equals a hotter device, which potentially may not last as long as a cooler device. Less devices dying after 3 years = less money for apple, so it is in their interest financially for their engineers to also consider planned obsolescence and ways to make consumers buy something new again. They are a company. They are not a not-for-profit scientific research institute. It s not in their interest design devices made to last 10-15 years, but lucky for us, sometimes they do last that long, and they may last longer if we try to keep them running cool. I’ll air on the side of caution.

Sigh ... again, heat is not the same thing as temperature. What matters is watts not degrees C. The CPU being at 100 C, which it is rated for, does not meant the batteries or SSD or any other component is that hot. Yes keeping your device and your case, especially for your laptop cool is good. That's why for discussing heat transferring from CPU to the surrounding components, WATTS and JOULES are important NOT TEMPERATURE.


"
Heat describes the transfer of thermal energy between molecules within a system and is measured in Joules.[2] Heat measures how energy moves or flows. An object can gain heat or lose heat, but it cannot have heat. Heat is a measure of change, never a property possessed by an object or system. Therefore, it is classified as a process variable.

Temperature describes the average kinetic energy of molecules within a material or system and is measured in Celsius (°C), Kelvin(K), Fahrenheit (°F), or Rankine (R). It is a measurable physical property of an object—also known as a state variable. Other measurable physical properties include velocity, mass, and density, to name a few.[3]"


An M1 Max CPU package can at most output 40W give or take, combined with the GPU about 90W peak. When discussing the temperature of components being affected by the processor, that is what the cooling system cares about, not what temperature the internal hotspot sensor buried in the SOC reads. For the SOC itself, it is rated for that temperature and according to those who design such systems can run practically forever at that temperature and yes the cooling system and performance controls are likewise designed to keep your SOC within those limits.

So in answer to your query I can absolutely construct a device that pipes all the heat from an Alder Lake i9 CPU into batteries keeping the CPU a nice cool 40 C while making the rest of the device a bomb. So measure the temperature of the actual component you are concerned about and if it is indeed over its limits, then by all means be concerned. Reporting the temperature of the hotspot sensor within the SOC tells you nothing about what is happening to the other components. Those Intel chips are outputting significantly more energy at 90C than the M1 Max is at 100C.
 
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Analog Kid

macrumors G3
Mar 4, 2003
9,360
12,603
Survey:
Which situation do you think your computer has the best chance of a long life,

A) the cpu and surrounding components are constantly blazing hot, close to 100C. This situation persists often for a weeks at a time, hours upon hours, days after days, weeks on end. It will constantly run blazing hot, close to 100 C.

B) the cpu and surrounding components are generally at 30~40 C. The temperature comes up for heavy loads. Fan curves are adjusted to keep the temperature down. Thermal paste is re-applied after some years to improve thermal performance.

C) there will not be a difference between A) and B) in affecting the lifespan of the product.

I think that based on what intel wrote on their website, The safer choice is B.
last sentence from the link below,
"....PC cooling isn’t just good practice. It’s also important for getting the best performance from your build, and for potentially increasing the lifespan of your components."

https://www.intel.com/content/www/u...g-the-importance-of-keeping-your-pc-cool.html

There is a potential that helping to keep your system cool will help it last longer. Not a certainty, but a potential. I think that as a company, Apple would like all of us to replace our devices every 2-4 years, and even with apple silicon, a quieter device also equals a hotter device, which potentially may not last as long as a cooler device. Less devices dying after 3 years = less money for apple, so it is in their interest financially for their engineers to also consider planned obsolescence and ways to make consumers buy something new again. They are a company. They are not a not-for-profit scientific research institute. It s not in their financial interest to design devices made to last 10-15 years, but lucky for us, sometimes they do last that long, and they may last longer if we try to keep them running cool. potentially I’ll air on the side of caution.
I’m going to vote A. Not for any reason having to do with temperature, but because scenario B involves both running the system outside the manufacturers design parameters and opening up the case to touch the internal components. Both of which seem higher risk than the temp difference you’re describing for a device designed to operate at 100C.

I’m not sure why you put so much weight on a throwaway line, hedged with the use of the word ”potentially”, in the summary of an Intel document when you’re discussing an Apple component.
 

throAU

macrumors G3
Feb 13, 2012
9,198
7,353
Perth, Western Australia
Survey:
Which situation do you think your computer has the best chance of a long life,

A) the cpu and surrounding components are constantly blazing hot, close to 100C. This situation persists often for a weeks at a time, hours upon hours, days after days, weeks on end. It will constantly run blazing hot, close to 100 C.

B) the cpu and surrounding components are generally at 30~40 C. The temperature comes up for heavy loads. Fan curves are adjusted to keep the temperature down. Thermal paste is re-applied after some years to improve thermal performance.

C) there will not be a difference between A) and B) in affecting the lifespan of the product.

I think that based on what intel wrote on their website, The safer choice is B.
last sentence from the link below,
"....PC cooling isn’t just good practice. It’s also important for getting the best performance from your build, and for potentially increasing the lifespan of your components."

https://www.intel.com/content/www/u...g-the-importance-of-keeping-your-pc-cool.html

There is a potential that helping to keep your system cool will help it last longer. Not a certainty, but a potential. I think that as a company, Apple would like all of us to replace our devices every 2-4 years, and even with apple silicon, a quieter device also equals a hotter device, which potentially may not last as long as a cooler device. Less devices dying after 3 years = less money for apple, so it is in their interest financially for their engineers to also consider planned obsolescence and ways to make consumers buy something new again. They are a company. They are not a not-for-profit scientific research institute. It s not in their financial interest to design devices made to last 10-15 years, but lucky for us, sometimes they do last that long, and they may last longer if we try to keep them running cool. potentially I’ll air on the side of caution.

Why do you think 100C is the magic number, because it's the boiling point of water, or some actual legitimate scientific reason?

Also, as per above, the SOC hot spot is not the same as the surrounding components.
 
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TimmuJapan

macrumors 6502
Jul 7, 2020
373
651
I’m not sure why you put so much weight on a throwaway line, hedged with the use of the word ”potentially”, in the summary of an Intel document when you’re discussing an Apple component.

@throAU , @Analog Kid , @crazy dave, @mr_roboto

I'll take you all on! LOL.... and I'll crash and burn just like Optimus prime did when he said the same thing.?.....





First of all....... The space shuttle is designed to take the heat / temperature of the earth's atmosphere upon re-entry, but that hasn't always worked out so well for the space shuttle, as we know.?

Secondly, @throAU , I'm not going to answer your questions, if you won't answer mine. :p ??

Thirdly, @Analog Kid , all of my MacBooks are intel!????

Fourthly, I am an Apple Fan boi. I love apple devices. I also recognize that they are a for profit-company, the most successful for-profit company in the world, and that they would rather sell us a new device than build us one that will last as long as we would like--the replacement cycle is what makes them a 2~3 trillion dollar company. There are ways to to keep things like ram, SSD, etc. modular, upgradeable, thin and light, and just as fast as the soldered on stuff. They don't do this anymore because once they started making the iPhone, they noticed that when their devices aren't upgradable anymore, the replacement cycle shortens significantly, and this is great for their profits. If it is true what intel writes, "PC cooling isn’t just good practice. It’s also important for getting the best performance from your build, and for potentially increasing the lifespan of your components" . If I were an apple engineer, trying to help my company make as much money as possible, I would prioritize a wonderful 3 year user experience over every thing else, because if the devices are more likely to be negatively affected and possibly die earlier due to excessive heat (it is hot when the temperature is high, b%tch#s!), that would be great for my company's bottom line over time. And the bottom line is what companies are all about. ??????

Some of us are using MacBooks from 2012 or earlier still. Why? Well, Because they made them great in that era, and we upgraded the devices and often went against Apple’s advice. We changed the devices in very basic ways--software and hardware. We did what Apple told us NOT to do. We opened up the back, We upgraded the ram, we put in an SSD, we installed open core legacy patcher, or a dosdude1 patch, we overrode our fans, we broke the rules, and we kept the device from becoming obsolete the way Apple intended and took our devices into the future succesfully. Nowadays, we can't upgrade the ram or the storage anymore, but believe you me, if we want to hold on to our current apple devices for as long as we held on to the ones from generations before, we will have to alter them somehow beyond Apple's original conception. If we just leave it to Apple entirely, we would be stuck with a MacBook Pro from 2012 with an HDD that has 4 GB of ram, and a Genius Bar representative just telling us “it’s really time for you to buy a new device“ーwhen in fact, that baby can take a SATA SSD, 16 gb of ram, opencore legacy patcher and remain a wonderfully useful machine years after apple intended it to be…..It is always a battle with both software and hardware against their planned obsolescence, and I believe thermals are part of this.????

Perhaps, I am wrong to override my fans to keep my devices cool.... Only time will tell.

Who's gonna hit me next? I'm ready for it! LOL! Come on, come on!
????
 
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bobcomer

macrumors 601
May 18, 2015
4,949
3,699
Survey:
Which situation do you think your computer has the best chance of a long life,

A) the cpu and surrounding components are constantly blazing hot, close to 100C. This situation persists often for a weeks at a time, hours upon hours, days after days, weeks on end. It will constantly run blazing hot, close to 100 C.

B) the cpu and surrounding components are generally at 30~40 C. The temperature comes up for heavy loads. Fan curves are adjusted to keep the temperature down. Thermal paste is re-applied after some years to improve thermal performance.

C) there will not be a difference between A) and B) in affecting the lifespan of the product.
C. (assuming someone doesn't mess up opening the machine and re-applying the thermal paste.)
 

steve62388

macrumors 68040
Apr 23, 2013
3,100
1,962
They've never got it right in the past, though. Dead GPUs from overheating and damaging the substrate. Warped logic boards that GPUs rise from or have broken solder connections. The CPU might survive but the chips and components around certainly wont appreciate the heat.

Apple always prioritises quiet running over longevity.
100% this.

I have a 2017 MacBook Pro which has very recently developed a faulty TCON (black bar along the bottom of the screen). This is definitely heat related, it failed when I was doing some heavy duty video encoding, disappears when it cools down, and then comes back again when it heats up. It’s a known fault. So the CPU might survive high temps, but as has been proven time and again with other Apple products a lot of the time other components in the system don’t. The system should never have been allowed to get that hot and throttled the CPU down before it did.

When I get a new M1 I’ll be setting a more aggressive custom fan profile.
 
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mi7chy

macrumors G4
Oct 24, 2014
10,622
11,294
@throAU , @Analog Kid , @crazy dave, @mr_roboto

I'll take you all on! LOL.... and I'll crash and burn just like Optimus prime did when he said the same thing.?.....

It's the same group that was spreading misinformation about 8GB = 16GB. When challenged with common sense they throw a tantrum and proclaim they're "real engineers" but in the end stop spouting nonsense.
 

Analog Kid

macrumors G3
Mar 4, 2003
9,360
12,603
Why do you think 100C is the magic number, because it's the boiling point of water, or some actual legitimate scientific reason?

Also, as per above, the SOC hot spot is not the same as the surrounding components.
It‘s three freaking digits, bruh! Twenty whole hands worth of fingers!
 
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Analog Kid

macrumors G3
Mar 4, 2003
9,360
12,603
Thirdly, @Analog Kid , all of my MacBooks are intel!????
I look at the forum title, then look at the thread title, then look at the OPs first post and I have to ask: are you sure you’ve only had 4 glasses of wine?

the replacement cycle is what makes them a 2~3 trillion dollar company
Brand loyalty, iPhones and services are what make them a $2T company. Replacements on Macs barely registers. Equipment failure is not good for brand loyalty, or service revenue, thus not good for profits.

Some of us are using MacBooks from 2012 or earlier still. Why? Well, Because they made them great in that era, and we upgraded the devices and often went against Apple’s advice. We changed the devices in very basic ways--software and hardware. We did what Apple told us NOT to do. We opened up the back, We upgraded the ram, we put in an SSD, we installed open core legacy patcher, or a dosdude1 patch, we overrode our fans, we broke the rules, and we kept the device from becoming obsolete the way Apple intended and took our devices into the future succesfully. Nowadays, we can't upgrade the ram or the storage anymore, but believe you me, if we want to hold on to our current apple devices for as long as we held on to the ones from generations before, we will have to alter them somehow beyond Apple's original conception. If we just leave it to Apple entirely, we would be stuck with a MacBook Pro from 2012 with an HDD that has 4 GB of ram, and a Genius Bar representative just telling us “it’s really time for you to buy a new device“ーwhen in fact, that baby can take a SATA SSD, 16 gb of ram, opencore legacy patcher and remain a wonderfully useful machine years after apple intended it to be…..It is always a battle with both software and hardware against their planned obsolescence, and I believe thermals are part of this.

Post hoc ergo propter hoc.

I’m also using equipment from that era and before and have broken few if any ”rules”.
 

Analog Kid

macrumors G3
Mar 4, 2003
9,360
12,603
100% this.

I have a 2017 MacBook Pro which has very recently developed a faulty TCON (black bar along the bottom of the screen). This is definitely heat related, it failed when I was doing some heavy duty video encoding, disappears when it cools down, and then comes back again when it heats up. It’s a known fault. So the CPU might survive high temps, but as has been proven time and again with other Apple products a lot of the time other components in the system don’t. The system should never have been allowed to get that hot and throttled the CPU down before it did.

When I get a new M1 I’ll be setting a more aggressive custom fan profile.
Was the cause heat related, or are the symptoms heat related? This sounds like a mechanical failure of a connection that then separates more easily when warm.

If it’s a known fault, then presumably Apple is aware of it and has taken steps to mitigate it in the past 5 years.

I’m pretty sure that the display cable is close to the exhaust of the fans, so if it’s truly heat related then doesn’t running the fans vector more of the system heat toward that cable? The point of the airflow is to take the heat from the SoC and move it to other places….
 

steve62388

macrumors 68040
Apr 23, 2013
3,100
1,962
Was the cause heat related, or are the symptoms heat related? This sounds like a mechanical failure of a connection that then separates more easily when warm.

If it’s a known fault, then presumably Apple is aware of it and has taken steps to mitigate it in the past 5 years.

I’m pretty sure that the display cable is close to the exhaust of the fans, so if it’s truly heat related then doesn’t running the fans vector more of the system heat toward that cable? The point of the airflow is to take the heat from the SoC and move it to other places….
The symptoms are indicative of a faulty TCON. Apple in their wisdom placed it near the hot air exhaust.

There are a lot of reports about the problem but they haven’t issued a repair program. Even if they did I suspect the age of my laptop would exclude it so I just have to suck it up.

It’s not worth getting repaired because you have to replace the entire mainboard.
 
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Analog Kid

macrumors G3
Mar 4, 2003
9,360
12,603
The symptoms are indicative of a faulty TCON. Apple in their wisdom placed it near the hot air exhaust.

There are a lot of reports about the problem but they haven’t issued a repair program. Even if they did I suspect the age of my laptop would exclude it so I just have to suck it up.

It’s not worth getting repaired because you have to replace the entire mainboard.
If this is the so-called flexgate failure, then the failure is caused by mechanical fatigue which Apple corrected in 2018 by making that flex a little longer.

The timing controller board is near the heat exhaust because the fans blow the heat away from the user and the display is hinged there because it's the only place that makes sense. If your concern is that heat makes this failure more common then your solution seems an odd approach-- you're saying you want to run the fans higher and push more hot air toward the component you think fails due to heat at the exhaust point...
 
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mr_roboto

macrumors 6502a
Sep 30, 2020
856
1,866
It's the same group that was spreading misinformation about 8GB = 16GB. When challenged with common sense they throw a tantrum and proclaim they're "real engineers" but in the end stop spouting nonsense.
lol what

I have consistently told everyone who will listen, at probably excessive length, that the 8GB + Apple Silicon magic = 16GB idea is wrong because magic (AS or not) isn't real.

Here's a 2020 post from me on the topic:


Why are you lying about me, mi7chy?
 

TimmuJapan

macrumors 6502
Jul 7, 2020
373
651
I look at the forum title, then look at the thread title, then look at the OPs first post and I have to ask: are you sure you’ve only had 4 glasses of wine?
I had had exactly 4 glasses of wine when I wrote that post and much more by the end, damnit!
 

steve62388

macrumors 68040
Apr 23, 2013
3,100
1,962
If this is the so-called flexgate failure, then the failure is caused by mechanical fatigue which Apple corrected in 2018 by making that flex a little longer.

The timing controller board is near the heat exhaust because the fans blow the heat away from the user and the display is hinged there because it's the only place that makes sense. If your concern is that heat makes this failure more common then your solution seems an odd approach-- you're saying you want to run the fans higher and push more hot air toward the component you think fails due to heat at the exhaust point...
No, it’s not flexgate (another mistake of Apple’s). Completely different symptoms. It was a poor engineering design choice by Apple to place the TCON where they did.

I said it should have throttled. Go back and re-read my post.
 
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Analog Kid

macrumors G3
Mar 4, 2003
9,360
12,603
No, it’s not flexgate (another mistake of Apple’s). Completely different symptoms. It was a poor engineering design choice by Apple to place the TCON where they did.

I said it should have throttled. Go back and re-read my post.
The system should never have been allowed to get that hot and throttled the CPU down before it did.

When I get a new M1 I’ll be setting a more aggressive custom fan profile.

And you concluded that you'll use a more aggressive custom fan profile...
 

steve62388

macrumors 68040
Apr 23, 2013
3,100
1,962
And you concluded that you'll use a more aggressive custom fan profile...
A more aggressive fan profile leads to lower overall temps. This is precisely what I am doing with my current MacBook to prevent the fault from manifesting itself. All temperature sensors (including Airflow) are lower under load.

Frankly, you're just being pugnacious. Go and waste somebody else's time because I'm not interested.
 
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Analog Kid

macrumors G3
Mar 4, 2003
9,360
12,603
A more aggressive fan profile leads to lower overall temps. This is precisely what I am doing with my current MacBook to prevent the fault from manifesting itself. All temperature sensors (including Airflow) are lower under load.

Good to know it worked for you. Airflow temp sensors are lower because you're pushing more air mass through, but the heat flow is actually higher (otherwise it wouldn't be more effective at cooling...). Fortunately it sounds like that heat isn't being delivered to your timing controller board.
 

januarydrive7

macrumors 6502a
Oct 23, 2020
537
578
100% this.

I have a 2017 MacBook Pro which has very recently developed a faulty TCON (black bar along the bottom of the screen). This is definitely heat related, it failed when I was doing some heavy duty video encoding, disappears when it cools down, and then comes back again when it heats up. It’s a known fault. So the CPU might survive high temps, but as has been proven time and again with other Apple products a lot of the time other components in the system don’t. The system should never have been allowed to get that hot and throttled the CPU down before it did.

When I get a new M1 I’ll be setting a more aggressive custom fan profile.
The heat-related T-CON fault has always been described as being related to issues with blocked venting (either due to e.g., excessive dust in fins or e.g., using laptop on a pillow, etc. -- I've even seen reports of T-CON issues going away with a good cleaning of fins.

There's still an issue here, though: if the cooling system can't remove energy fast enough from the system, then the CPU will throttle, to keep it <= 100C. If, from your aggressive fan profile, fans are running 100%, and the system still can't remove energy fast enough, then the CPU will still throttle, to keep it <= 100C. There is no controller that I'm aware of that will throttle the CPU in order to keep the TCON <= [whatever temp causes TCON issue]. Fan controller software doesn't force CPU throttling, it just forces the rate of energy transfer, which could still heat up your TCON beyond the threshold for the issue to present itself.

Case in point: my 2.3Ghz i9 in my 2019 MBP was running a heavy load over the last 24 hours straight, with temps at a constant 100C, fans at a constant 100%, and boosting between 3.4-4.0 (well above the rate 2.3 baseline, but below the boost of 4.8). So, even with 100% fan speed (as aggressive your fans can get), you'll still see high temps if the load is demanding enough, because CPUs are meant to run up to ~100C without throttling.
 

leman

macrumors Core
Oct 14, 2008
19,521
19,675
But don't take it from me..... Take it from intel:
last sentence from the link below,
"....PC cooling isn’t just good practice. It’s also important for getting the best performance from your build, and for potentially increasing the lifespan of your components."

https://www.intel.com/content/www/u...g-the-importance-of-keeping-your-pc-cool.html

All this article says that cooling is important for reaching expected performance. This is absolutely true. And Apple computers provide sufficient cooling to reach that performance. What’s the problem? Why do you insist to run the hardware outside if it’s optimal range?
 

leman

macrumors Core
Oct 14, 2008
19,521
19,675
Survey:
Which situation do you think your computer has the best chance of a long life,

A) the cpu and surrounding components are constantly blazing hot, close to 100C. This situation persists often for a weeks at a time, hours upon hours, days after days, weeks on end. It will constantly run blazing hot, close to 100 C.

B) the cpu and surrounding components are generally at 30~40 C. The temperature comes up for heavy loads. Fan curves are adjusted to keep the temperature down. Thermal paste is re-applied after some years to improve thermal performance.

C) there will not be a difference between A) and B) in affecting the lifespan of the product.

I think that based on what intel wrote on their website, The safer choice is B.
last sentence from the link below,
"....PC cooling isn’t just good practice. It’s also important for getting the best performance from your build, and for potentially increasing the lifespan of your components."

https://www.intel.com/content/www/u...g-the-importance-of-keeping-your-pc-cool.html

There is a potential that helping to keep your system cool will help it last longer. Not a certainty, but a potential. I think that as a company, Apple would like all of us to replace our devices every 2-4 years, and even with apple silicon, a quieter device also equals a hotter device, which potentially may not last as long as a cooler device. Less devices dying after 3 years = less money for apple, so it is in their interest financially for their engineers to also consider planned obsolescence and ways to make consumers buy something new again. They are a company. They are not a not-for-profit scientific research institute. It s not in their financial interest to design devices made to last 10-15 years, but lucky for us, sometimes they do last that long, and they may last longer if we try to keep them running cool. potentially. I’ll air on the side of caution.

And a computer that is never turned on will probably have a longer lifespan than one that is used for daily work. What’s your point?

Look, electromigration is real. Temperature does damage electronic components. And running at 100C will obviously reduce the lifespan compared to running at 20C. But we are operating with quantities here that have no practical relevance. Even if you regularly push you chips to run close to 100C, they will still have many many years of useful life in them. Your computer is much more likely to fail because to some micro-flaws in manufacturing process rather than to effects of electro-migration. Apple has been using the same heat management tactics for over a decade - all their internals run hot. And they still are regarded as one of the most reliable companies out there despite this. Already this fact should make it clear that the detrimental effects of “heat” are vastly overstated.
 
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