I recently installed an app to manually activate the fans on my MacBook Pro M1 Pro as I've never been able to trigger them over the past 4+ years. Just to check whether the fans even work (they do).
amluto•May 27, 2026
You must be using only lame languages like C or Go or Python that aren’t optimized for laptop warming during compilation. Try using a Real Language with a Real Compiler, like C++ or Rust or Swift, and build decent-sized projects using all cores.
(All joking aside, this is why I have a MacBook Pro. Compilation easily hits the Air’s thermal limits and the performance boost on the Pro with its fan is impressive.)
woozlewuzzle•May 27, 2026
You could also build Chromium from source. It makes my M1 Max's fans sing.
asdff•May 28, 2026
I get them going full blast in 2 minutes from cities skylines.
tom_•May 28, 2026
I left my Mac Studio running at 100% CPU on all cores for 14 hours, and the case ended up noticeably warm to the touch. It is possible!
asdff•May 28, 2026
Try increasing to 10 cores. Works on my m3 pro.
ale•May 27, 2026
Honestly i prefer my macbook frosty
selimthegrim•May 28, 2026
Sir, this is a Wendy's
jvuygbbkuurx•May 27, 2026
I just need to build our monorepo
Onavo•May 27, 2026
I think any next.js project will do the trick
amomchilov•May 27, 2026
How big is the risk of condensation when you bring a cold laptop inside?
All their spec sheets say they support up to x% _non-condensing_ humidity, which I’m guessing is about the dew point?
ericpauley•May 27, 2026
The uncomfortable fact about the mentioned Wisconsin winters is that inside dew point tends to be quite low.
vibcdingenjoyer•May 28, 2026
I’ve always been told to let electronics and musical instruments slowly warm up in their case after bringing them inside. Supposedly reduces the chances of condensation forming.
1e1a•May 27, 2026
Another (more useful) option is to render an animation in Blender, or run a local LLM.
Scubabear68•May 27, 2026
Needs 2019 in title, this is Intel MacBooks not Apple Silicon.
dunham•May 27, 2026
I've found that Baldur's Gate 3 will warm up my apple silicon (everyday tasks do not).
Analemma_•May 27, 2026
Is that running on Rosetta 2? Rosetta 2 does (or did, maybe it's removed now) a fine job running x86 code on Apple Silicon, but boy was it cycle-hungry to do it.
dangus•May 27, 2026
Apple Silicon is not really the simultaneously silent and quiet and cool system it was in the M1 days.
If you get a MacBook Air it will get quite toasty at throttling limits. After all, it has no fan.
MacBook Pro models and Apple computers in general tend to favor quiet operation over keeping the laptop surface cool.
Many PC gaming laptops go out of their way to keep warm air off the keyboard deck with a high willingness to use fan noise to accomplish that since the assumption is that you’re resting your hands on the computer for an extended period and you have headphones on for your game anyway.
dunham•May 28, 2026
I probably should have clarified that I'm on an M1 then (a macbook pro, so there is a fan). I didn't realize the newer ones get warmer.
asimovDev•May 28, 2026
BG3 is a native game, they dropped x86 support shortly after launch on macOS (or maybe even in beta)
reboot81•May 27, 2026
Looking forward to the follow up: How to Quickly Cool Down Your MacBook
ge96•May 27, 2026
Strap a thermopile and a peltier on that bad boy
sunrunner•May 27, 2026
Just do the trick in reverse, surely?
yes no > /dev/null
why_at•May 27, 2026
No you have to get the yesses back out
cat /dev/null | yes
kotaKat•May 28, 2026
You might have to load in maybe.so for that to work though.
crote•May 28, 2026
Unironically, yes.
My M3 Macbook Pro's palm rests get uncomfortably warm during regular IDE use. It doesn't get hot enough to spin up a fan, but it is enough to be distracting.
asimovDev•May 28, 2026
interesting. for me only the bottom and the top part above the keyboard gets warm during my work. 16inch model. Is yours the 14inch one?
nottorp•May 28, 2026
I have the 14 inch and i've never felt it go warm.
I think the real question is what IDE we're talking about.
asimovDev•May 28, 2026
I am mostly in PHPStorm with several projects open + sometimes I have Xcode and/or Android Studio open as well
nottorp•May 28, 2026
Haven't used PHPStorm but I know Android Studio does a lot of stuff in the background so I wouldn't be surprised if other JetBrains IDEs do the same. Although PHP isn't compiled...
asimovDev•May 28, 2026
There's still indexing, linting and code analysis tools running as well as multiple Docker containers (those are pretty much idle outside of running tests or migrations to be fair) and whatever else it could be doing in the background.
I spend 95% of the time with just PHPStorm and other stuff like the terminal, slack and ticketing open. And the browser of course (safari). Xcode and Android Studio are rarely opened. Mostly when I want to test out something in the apps that isn't on testflight / firebase yet.
crote•May 28, 2026
14 inch, running primarily IntelliJ IDEA and Firefox. Around 10% CPU use most of the time, with of course the occasional spike for compilation.
It's not hot, but with 22C ambient it is enough of a rise to be annoying.
HDBaseT•May 27, 2026
For years at work I've been just using Cinebench as a hand warmer on various Macbooks.
hakkoru•May 28, 2026
I always enjoyed using the power brick to warm up
mark242•May 27, 2026
npm install
waterhouse•May 27, 2026
Multithreaded:
seq 1 20 | xargs -Iqq -n1 -P0 yes >/dev/null
kingjimmy•May 27, 2026
"This will start 6 threads that each peg your CPU... "
they're doing what to my CPU????
crest•May 27, 2026
Bend over for big tech!
imp0cat•May 28, 2026
Fully utilize.
Also, pour one for the death of the analog speedo. Peg the needle, no more!
andrewstuart2•May 28, 2026
Now that's a fun microcontroller project idea. An analog dashboard for ram/cpu/whatever. I'm sure it's been done.
while true; do openssl speed ecdsap384 -multi 2; done
kristianp•May 27, 2026
Or you could get a laptop that doesn't have an metal shell, like a thinkpad.
Cassell•May 27, 2026
they often have a magnesium bottom shell
simulator5g•May 28, 2026
Or just leave the machine plugged in and turned on for like 5 minutes while you grab a coffee or have a conversation. It doesn't really take that long to warm up to room temperature. Unless this guy is like biking 15 miles to work in the winter in which case, he is doing Wisconsin wrong, you're supposed to drive to work with a beer to warm you up.
Hobadee•May 28, 2026
I'm from California... What is this "cold" you speak of?
int0x29•May 28, 2026
The Donner Party begs to differ
isomorphic•May 28, 2026
Floridian. I thought "frozen lake" was some sort of Intel CPU reference.
nottorp•May 28, 2026
You don't know how right you are. I don't think Apple ever tests their hardware outside the CA climate.
xgkickt•May 28, 2026
“Designed in California, for Californians” was too long.
splittydev•May 28, 2026
Alternatively, you could try compiling an Xcode project. That should do the trick as well.
jerlam•May 28, 2026
I think my last Macbook was Wisconsin-locale instead of California. Closing the lid and putting it to sleep actually caused it to heat up (until the battery died).
simulator5g•May 28, 2026
It had the soul of a PC
ralphc•May 28, 2026
I still use a 2019 MacBook Pro, in 2026 I found the best way to warm it up was to use it daily and not blow the dust out of it for 7 years. After I opened it up and did that it's running a lot cooler.
mcfedr•May 28, 2026
yes only writes y, not the whole word yes
fnord77•May 28, 2026
unless you type
yes yes
smarks•May 28, 2026
Warming up a 2019-era (Intel) MacBook Pro was never my problem. Quite the opposite. Those machines ran notoriously hot. The later macOS releases, combined with company-mandated crapware, made it worse. Doing an ordinary build or starting a videoconferencing session was enough to cause the fans to run. On a warm day the fans couldn’t shed enough heat and so the system would go into thermal throttling. The OS would occupy a core with a 100% kernel_task that didn’t do any work but which would serve to prevent actual work from being scheduled onto that core. When four or five out of the six cores were occupied by kernel_task, I knew I was in for a bag of hurt (to steal a phrase from Steve Jobs). Responsiveness went completely to hell. The machine became effectively unusable.
After a while my normal procedure was to run with the thing sitting on top of an ice pack. That would let me run a 60-90 minute video conference without troubles.
The only redeeming feature of these machines is that they could emulate old x86 hardware at speed. That allowed me to run old apps on old OSes without having to keep old hardware running.
recursivecaveat•May 28, 2026
My Intel MBP would noticeably raise the whole room's temperature, while the fans ran so loud. We had some corporate security software that would occasionally go haywire and lock up 100% of a core until you rebooted. If you got that at the same time as a video call it would become too physically painful to touch any part of the metal body with bare skin.
alexwwang•May 28, 2026
Maybe the same type. Each time I call the LLM api the fan starts to work and make big noise. The temperature in the room is going up noticeably for 1-2 degrees.
embedding-shape•May 28, 2026
> Each time I call the LLM api the fan starts to work and make big noise
So every time you do HTTP calls? Nothing there should spin up your fans, unless you use an agent with an horribly broken TUI, I've heard there is a few of those out there. But remotely calling LLM APIs really shouldn't be taxing on your local device, something somewhere is wrong/bad if that's what you're seeing.
alexwwang•May 28, 2026
If the horribly broken TUI you mentioned is OpenCode, I’d say yes. That’s exactly what I am experiencing.
embedding-shape•May 28, 2026
Sure, if that's what you're using, then that's definitively buggy, unless it's doing compilation or something actually using your resources, just making HTTP calls shouldn't be heavy for your computer. Claude Code was mainly what I was thinking about, as it similarly broken, but I'm sure there are more out there as most of them seem vibe-coded at best.
alexwwang•May 28, 2026
Yes. Whatever *code, the same when they are working. The node.js backend is awful.
Filligree•May 28, 2026
Is it a local LLM? Sibling seems to be assuming remote, but I have trouble imagining a TUI that inefficient.
alexwwang•May 28, 2026
No. Simply the rest api call in opencode tui. I don’t know why maybe the mbp is too old, at least it served 6 years +.
reitzensteinm•May 28, 2026
I had Windows and Mac laptops back then, and the HN snobbishness around the superiority of the Mac was genuinely baffling.
My i9 2019 MBP with discrete graphics was probably the worst laptop purchase I ever made. Docking it to an external monitor would enable the GPU, so even when idling it would run the fans and drain the battery.
I’d read cautionary tales about Windows laptops being pulled out of backpacks scorching hot as they failed to shut down. But that happened to my Mac all the time, too.
The M series though is incredible. I can’t imagine buying a Windows laptop now.
pja•May 28, 2026
The i9 was notorious. Would thermally throttle almost instantly & for any sizeable build job would end up slower than the i7 IIRC.
Intel really made themselves unpopular with Apple during that period.
close04•May 28, 2026
> Intel really made themselves unpopular with Apple during that period.
Intel just reenacted IBM's history with Apple, particularly the G5 era. That CPU was instantly a no-go for anything mobile. In workstations it was cranked ever higher with very poor power-frequency scaling, needing water cooling for the beastly 200W idle power consumption and close to 1kW full throttle.
That went well so was a perfect role model for Intel's i9.
aeyes•May 28, 2026
> Intel really made themselves unpopular with Apple during that period.
You can't tell me that this wasn't known by Apple before shipping the product. Why did they not provide adequate cooling for the CPU?
carlosjobim•May 28, 2026
Apple hardware quality on the laptops was bottom tier during the 2016-2019 "butterfly" era. There's no denying.
mfro•May 28, 2026
It was a truly ridiculous idea to put an i9 in any laptop. That generation of i9 is difficult to cool even with liquid cooler systems in big ATX cases.
smarks•May 28, 2026
Oh yeah, I forgot about the graphics.
I had (and still have) a 4k external monitor. Naturally I wanted the MBP to drive the monitor with a resolution that took advantage of all the pixels. Unfortunately with most monitor settings the GPU power consumption would produce enough heat to run the fans even if the rest of the system was completely idle! If I set the output to full HD the GPU would cool down and the fans would turn off. But full HD on a 4k monitor is a waste.
It was very strange. I could drive the monitor at 4k but with the image upside down, and the power consumption would be low. But flip the image right side up and it would run hot and turn on the fans.
It took a couple weeks of fiddling, but I finally found a combination of refresh rate, resolution, image orientation (right side up!), and cabling that let me drive the monitor at high resolution without running the fans. What a pain.
(I used iStat menus to monitor GPU power consumption. At “good” settings it consumed about 5w. At “bad” settings it would consume 17w. At a bad setting you could immediately see the various temperatures go up and the fans spinning up to compensate.)
blackoil•May 28, 2026
Those were John Ive era laptops where form ruled function. Poor thermal, less ports, less keys were all features.
philistine•May 28, 2026
Form always ruled function with Jony Ive, but he always had a good eye for the way compromises shook out. During that era, Ive was creatively checked out but Cook kept him on to maintain the stock price.
jorgeleo•May 28, 2026
i decided to do an experiment and try to run an LLM in my old 2013 MBP. i7, 16 gb mem, 1 tb hd.
Installed Linux mint Xfce Edition for lightness, installed ollama, start to test different models. Gemma4 e4b runs perfectly fine, exposed it to the network, connected to it with my current notebook and use vs code codex to start to run inference.
For about 30 minutes of bliss, this setup work at a reasonable speed... then the MBP shut it self down. It was so hot that it trigger the safety mechanism, the fans sounded like the laptop was about to take off.
I though on leaving it on inside the fridge, but then the WIFI wouldn't reach.
On the other hand, my wife saw all this and offer to buy me an M5... the experiment didn't work as intended, but it did work.
tacomagick•May 28, 2026
Could be in need of a thermal paste refresh etc.?
bartread•May 28, 2026
On a laptop that old it might be worth opening it up to blow all the dust out with a compressor or air duster. I’ve often found that to work wonders on old MacBook Pros.
The other issue is that unless the battery has been replaced relatively recently its charging efficiency may not be that great and the high load being placed on it might be causing it to get hotter than it would have done when new.
villgax•May 28, 2026
This is now running Cyberpunk or an LLM locally
diimdeep•May 28, 2026
Or something useful, save space, compressing some talk or edu video, just 6 fps is usually enough for slides or code, opus audio can go as low as 32k and still be decent compared to source quality, expect 10-15x size reduction
In homeoffice I always work in the nude and the cold metal of my macbook pro hurts my thighs…
fastjack42•May 28, 2026
Now do the opposite for the summer! Show me a command line that cools down the machine! ;)
p0w3n3d•May 28, 2026
Does this work with M series ? M series is much colder and my fingers hurt <sob>
gizajob•May 28, 2026
Running an LLM in the background is the contemporary version of this.
paul_knox•May 28, 2026
Just run Intel (x86) apps via Rosetta 2 in the background. You’ll feel that classic Intel warmth coming right back.
dasKrokodil•May 28, 2026
Speaking of cold weather and warming up computers... I've had my fair share of long bicycle commutes during cold winters and I always wondered whether booting up the laptop right after arriving has any effect on the long-term reliability? Like, are there any components which suffer from being activated when they're really cold?
nottorp•May 28, 2026
I always leave the laptop untouched for at least 10 minutes when coming in from the cold. Don't know if it helps but it makes me feel better.
lebuin•May 28, 2026
I try to leave my laptop untouched for as much as I possibly can. Definitely makes me feel better too.
ivanjermakov•May 28, 2026
At the first half of your comment I thought you would suggest using laptop as a back heater during cold weather rides!
Tade0•May 28, 2026
The battery might need warmup, but it would have to be significantly below freezing outside to affect it.
Electrolytic capacitors can freeze up but again, you'd need a Yakutia-like environment for it to actually pose a concern.
Lastly I've heard of circuit boards warping from going from really cold to really hot, but those were power components.
Filligree•May 28, 2026
It increases the chance of solder cracks, which is one major cause of failure. Thermal cycles in general will do that, however, and home computers are designed to survive a lot of them.
So overall it’s not something I’d worry about.
Cthulhu_•May 28, 2026
Modern Macbooks have this issue, the other day I realised I had never heard the fans of it run, so I was wondering if they actually worked.
Found a web based benchmark tool that will run your CPU and GPU at 100% each. While temperatures went up to 90 degrees science... still no fans. Ended up installing a different utility to manually set the fan speed to confirm they worked.
I don't know what they did but it's good.
nickdothutton•May 28, 2026
May I introduce you to local LLMs?
crefiz•May 28, 2026
Care to share the name of both tools? Cheers
niklasbuschmann•May 28, 2026
> openssl speed
traceroute66•May 28, 2026
To be fair, the fundamental problem here is the author's resting of wrists to type.
This applies to any computer, Apple, Windows or Linux. Desktop or laptop.
If your typing on any computer is dependent on you resting your wrists whilst typing then it is indicative of poor typing technique and/or posture.
And ironically the very thing you think you're trying to prevent by resting your wrists (carpel tunnel and/or strain) is likely to be aggravated by over-reliance on wrist wrests due to the added pressure on the wrist.
mexicocitinluez•May 28, 2026
Slightly quicker way to do this is opening Microsoft Teams.
30 Comments
(All joking aside, this is why I have a MacBook Pro. Compilation easily hits the Air’s thermal limits and the performance boost on the Pro with its fan is impressive.)
All their spec sheets say they support up to x% _non-condensing_ humidity, which I’m guessing is about the dew point?
If you get a MacBook Air it will get quite toasty at throttling limits. After all, it has no fan.
MacBook Pro models and Apple computers in general tend to favor quiet operation over keeping the laptop surface cool.
Many PC gaming laptops go out of their way to keep warm air off the keyboard deck with a high willingness to use fan noise to accomplish that since the assumption is that you’re resting your hands on the computer for an extended period and you have headphones on for your game anyway.
My M3 Macbook Pro's palm rests get uncomfortably warm during regular IDE use. It doesn't get hot enough to spin up a fan, but it is enough to be distracting.
I think the real question is what IDE we're talking about.
I spend 95% of the time with just PHPStorm and other stuff like the terminal, slack and ticketing open. And the browser of course (safari). Xcode and Android Studio are rarely opened. Mostly when I want to test out something in the apps that isn't on testflight / firebase yet.
It's not hot, but with 22C ambient it is enough of a rise to be annoying.
they're doing what to my CPU????
Also, pour one for the death of the analog speedo. Peg the needle, no more!
Edit: https://sasakaranovic.com/projects/diy-analog-resource-monit...
After a while my normal procedure was to run with the thing sitting on top of an ice pack. That would let me run a 60-90 minute video conference without troubles.
The only redeeming feature of these machines is that they could emulate old x86 hardware at speed. That allowed me to run old apps on old OSes without having to keep old hardware running.
So every time you do HTTP calls? Nothing there should spin up your fans, unless you use an agent with an horribly broken TUI, I've heard there is a few of those out there. But remotely calling LLM APIs really shouldn't be taxing on your local device, something somewhere is wrong/bad if that's what you're seeing.
My i9 2019 MBP with discrete graphics was probably the worst laptop purchase I ever made. Docking it to an external monitor would enable the GPU, so even when idling it would run the fans and drain the battery.
I’d read cautionary tales about Windows laptops being pulled out of backpacks scorching hot as they failed to shut down. But that happened to my Mac all the time, too.
The M series though is incredible. I can’t imagine buying a Windows laptop now.
Intel really made themselves unpopular with Apple during that period.
Intel just reenacted IBM's history with Apple, particularly the G5 era. That CPU was instantly a no-go for anything mobile. In workstations it was cranked ever higher with very poor power-frequency scaling, needing water cooling for the beastly 200W idle power consumption and close to 1kW full throttle.
That went well so was a perfect role model for Intel's i9.
You can't tell me that this wasn't known by Apple before shipping the product. Why did they not provide adequate cooling for the CPU?
I had (and still have) a 4k external monitor. Naturally I wanted the MBP to drive the monitor with a resolution that took advantage of all the pixels. Unfortunately with most monitor settings the GPU power consumption would produce enough heat to run the fans even if the rest of the system was completely idle! If I set the output to full HD the GPU would cool down and the fans would turn off. But full HD on a 4k monitor is a waste.
It was very strange. I could drive the monitor at 4k but with the image upside down, and the power consumption would be low. But flip the image right side up and it would run hot and turn on the fans.
It took a couple weeks of fiddling, but I finally found a combination of refresh rate, resolution, image orientation (right side up!), and cabling that let me drive the monitor at high resolution without running the fans. What a pain.
(I used iStat menus to monitor GPU power consumption. At “good” settings it consumed about 5w. At “bad” settings it would consume 17w. At a bad setting you could immediately see the various temperatures go up and the fans spinning up to compensate.)
Installed Linux mint Xfce Edition for lightness, installed ollama, start to test different models. Gemma4 e4b runs perfectly fine, exposed it to the network, connected to it with my current notebook and use vs code codex to start to run inference.
For about 30 minutes of bliss, this setup work at a reasonable speed... then the MBP shut it self down. It was so hot that it trigger the safety mechanism, the fans sounded like the laptop was about to take off.
I though on leaving it on inside the fridge, but then the WIFI wouldn't reach.
On the other hand, my wife saw all this and offer to buy me an M5... the experiment didn't work as intended, but it did work.
The other issue is that unless the battery has been replaced relatively recently its charging efficiency may not be that great and the high load being placed on it might be causing it to get hotter than it would have done when new.
Electrolytic capacitors can freeze up but again, you'd need a Yakutia-like environment for it to actually pose a concern.
Lastly I've heard of circuit boards warping from going from really cold to really hot, but those were power components.
So overall it’s not something I’d worry about.
Found a web based benchmark tool that will run your CPU and GPU at 100% each. While temperatures went up to 90 degrees science... still no fans. Ended up installing a different utility to manually set the fan speed to confirm they worked.
I don't know what they did but it's good.
This applies to any computer, Apple, Windows or Linux. Desktop or laptop.
If your typing on any computer is dependent on you resting your wrists whilst typing then it is indicative of poor typing technique and/or posture.
And ironically the very thing you think you're trying to prevent by resting your wrists (carpel tunnel and/or strain) is likely to be aggravated by over-reliance on wrist wrests due to the added pressure on the wrist.