Resolved 2019 MBP 16" incredibly hot, fans not turning on -- until I downloaded a program that let me manually turn the fans on!

[nkl95]

I've never had this experience before. I had a 2013 MBA for 7 years and upgraded to a 16" in spring 2020 to deal with Zoom University (I had the best Lenovo Yoga laptop for 2 years between this but the screen hinge broke :'(). I have been having consistent problems with my MBP heating up to unacceptably hot temperatures even while using in front of the AC unit and/or the fan on the table. Not once have the fans kicked in to cool it off and I would have to stop using it every hour to let it cool down. I use the Touch Bar frequently in my typing for text shortcuts and the space between the Touch Bar and monitor would nearly burn my fingers.

I'm currently backing up my Google account to my new MBP after months of putting it off. Finally, this morning, I spent an hour(!!) looking into why my MBP is so dang hot. I've never heard the fans kick on before I manually forced them to using a program such as iStat. Now, instead of 150+F temperatures, it's hovering around 115-120F and continuing to get cooler.

Most of the articles and forum posts I found were regarding external monitors. I do not use one. I've run diagnostics monthly and there are no errors. I don't use Chrome very often (perhaps only 10 hours per week while in classes) and I usually spend my time on Zoom in meetings or on Word writing papers and reports.

The worst area is between the Touch Bar and monitor. It used to get absurdly hot. I have a stand to keep the MBP elevated that is uncomfortable to type on but keeps it cool. Moderate trade off.

Now that I can manually kick on the fans, there is a noticeable difference in both my MBP performance and how hot it feels. It has definitely cooled down significantly just in the 15 minutes or so that I've been running this program.

My main point in writing this is to save some other poor, fed up, possibly sleep-deprived soul an hour long goose chase on the internet running through all the different diagnostics and tips and tricks if you are NOT using an external monitor or using Chrome or have a million tabs open. Download an app that allows you to manually turn on the fans and you will see an IMMEDIATE difference if there are no errors running diagnostics. My biggest gripe now is that the one I found requires you to pay after a trial but the $10 will be worth finally being able to use my MBP for longer periods of time.

Thanks for having me.

 

[GumaRodak]

the computer is hot because of some reason, turning the fans to max doesn't really solve the root cause...

 

[nkl95]

the computer is hot because of some reason, turning the fans to max doesn't really solve the root cause...

The computer is hot because I am using it. The fans were not automatically turning it on. Manually turning the fans on is fixing the problem where it gets too hot to use.

 

[IowaLynn]

What is Activity Monitor show running rampant? An out of control or errant process?

Also, during last two IS upgrades, good reason to do a clean install. Old crusty incompatible apps and configurations.

But dry ice on your engine block can do wonders. But I think it's not addressing the cause - just brings the patient's down.

If it still has SMC or controlled by T2, those can need resetting.

 

[jerryk]

Macbook 16" always runs their fans. They start at around 1700 RPM. The issue is the Intel processor generates a lot of heat under load and Apple is OK with letting the system run into the 80C range before getting aggressive with temp management. Apple has determined this is fine as far as balancing system life (i.e. warranty claims) versus fan noise.

The good thing is we don't have to worry about this much longer. With the M1 processor, systems can achieve near 16" performance on some tasks without generating large amounts of heat. And therefore do not need to have a fan (MB Air M1) or if they have fans, run them at high RPMs with associated noise. This will hopefully stay the same as systems using the M1x, M2, ... SOCs are introduced.

 

[nkl95]

What is Activity Monitor show running rampant? An out of control or errant process?

That's the crazy thing ... there is nothing that is running wild. WindowServer takes about 20%, Activity Monitor does 10-ish%, Safari/Zoom/etc all do less. However, my MBP gets crazy hot after about thirty minutes (and dangerously hot after a full day of Zoom meetings!). Today, after a long Zoom session with my fans running, I can actually still use my laptop without hurting my fingers on the hot spots. The temperature has yet to spike up to the 150F it was when iStat first started running, too. The hottest it got was 120F while screen sharing for nearly an hour. The fan noise on the Medium setting (50%) was barely even noticeable and it made such a huge difference.

Macbook 16" always runs their fans. They start at around 1700 RPM. The issue is the Intel processor generates a lot of heat under load and Apple is OK with letting the system run into the 80C range before getting aggressive with temp management. Apple has determined this is fine as far as balancing system life (i.e. warranty claims) versus fan noise.

The good thing is we don't have to worry about this much longer. With the M1 processor, systems can achieve near 16" performance on some tasks without generating large amounts of heat. And therefore do not need to have a fan (MB Air M1) or if they have fans, run them at high RPMs with associated noise. This will hopefully stay the same as systems using the M1x, M2, ... SOCs are introduced.

That would be nice! I'm waiting for a 16 inch M1 to upgrade (again?). I've never had a laptop get so incredibly hot under such a light load. I know Zoom is the culprit for the most part but when I'm just working on Word documents, it shouldn't be getting so hot!

 

[GumaRodak]

my fans starting to kick if the cpu gets around 70C for longer time, otherwise they idle..no issue using th ecomputer like this for months...disabling turbo boost removes like 20C

 

[IowaLynn]

my fans starting to kick if the cpu gets around 70C for longer time, otherwise they idle..no issue using th ecomputer like this for months...disabling turbo boost removes like 20C

If you could disable hyper-threading along with turbo boost... H/T adds a lot of heat for a small improvement.

That is why i went with an i5 6-core instead of i7, no h/t, no pseudo, virtual cores. The fan stays quiet though the heat out the back of Mac Mini is still very warm

 

[Fear12]

my fans starting to kick if the cpu gets around 70C for longer time, otherwise they idle..no issue using th ecomputer like this for months...disabling turbo boost removes like 20C

Do you just use “Turbo Boost Switcher” application that I’m reading about everywhere or do you use some other method?

 

[GumaRodak]

Do you just use “Turbo Boost Switcher” application that I’m reading about everywhere or do you use some other method?

Turbo boost switcher

 

[lpearse]

I had Turbo Boost Switcher and it worked great, but then my computer failed 2019 MBP16 and had a new logic board installed and now TBS does not work. I have reinstalled it but nope. Running Catalina.

 

[iMacDragon]

If they're not ramping up when cpu is getting to 70-80c something is wrong in T2/SMC, try resetting it.

But apples fan ramp is overly conservative to quietness, also.

 

[sgtaylor5]

If they're not ramping up when cpu is getting to 70-80c something is wrong in T2/SMC, try resetting it.

But apples fan ramp is overly conservative to quietness, also.

This^^

Apple’s fan ramp curve is so conservative; I’m using Macs Fan Control from CrystalIdea and it is worth it. I try to keep my temperature at 43 - 55 C at rest -average use.