Warm up your MacBook (2019)
59 points
9 hours ago
| 23 comments
| z3ugma.github.io
| HN
smarks
57 minutes ago
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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.

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dnnddidiej
7 hours ago
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For those without spacebar heating?
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mrtksn
6 hours ago
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They broke that workflow in a recent update. Software these days is horrendous
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ralphc
1 hour ago
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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.
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kingjimmy
7 hours ago
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"This will start 6 threads that each peg your CPU... "

they're doing what to my CPU????

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crest
7 hours ago
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Bend over for big tech!
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amomchilov
9 hours ago
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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?

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ericpauley
6 hours ago
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The uncomfortable fact about the mentioned Wisconsin winters is that inside dew point tends to be quite low.
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HDBaseT
7 hours ago
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For years at work I've been just using Cinebench as a hand warmer on various Macbooks.
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hakkoru
6 hours ago
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I always enjoyed using the power brick to warm up
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waterhouse
7 hours ago
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Multithreaded:

  seq 1 20 | xargs -Iqq -n1 -P0 yes >/dev/null
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jvuygbbkuurx
9 hours ago
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I just need to build our monorepo
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Onavo
9 hours ago
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I think any next.js project will do the trick
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Traubenfuchs
24 minutes ago
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In homeoffice I always work in the nude and the cold metal of my macbook pro hurts my thighs…
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diimdeep
31 minutes ago
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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

  ffmpeg -hide_banner -y -i in.mp4 \
    -vf "fps=6,format=yuv420p,scale=960:-2:flags=lanczos" \
    -c:v libx265 -tag:v hvc1 -crf 32 -pix_fmt yuv420p -preset fast \
    -c:a libopus -b:a 82K -application 2048 \
    -c:s mov_text \
    out.mp4
can go more crazy with this soup

  -x265-params "keyint=800:min-keyint=24:scenecut=20:ref=8:bframes=16:b-adapt=2:rc-lookahead=80:rd=4:subme=5:deblock=1,1:aq-mode=3:aq-strength=0.4:psy-rd=0.4:psy-rdoq=1.0:qcomp=0.7:qg-size=64:rect=1:amp=1:strong-intra-smoothing=1:limit-modes=1:limit-tu=4:rdpenalty=2:tu-intra-depth=4:tu-inter-depth=4:me=star:no-allow-non-conformance=1" \
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reboot81
8 hours ago
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Looking forward to the follow up: How to Quickly Cool Down Your MacBook
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sunrunner
8 hours ago
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Just do the trick in reverse, surely?

  yes no > /dev/null
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why_at
7 hours ago
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No you have to get the yesses back out

  cat /dev/null | yes
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ge96
8 hours ago
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Strap a thermopile and a peltier on that bad boy
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Hobadee
6 hours ago
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I'm from California... What is this "cold" you speak of?
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isomorphic
26 minutes ago
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Floridian. I thought "frozen lake" was some sort of Intel CPU reference.
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int0x29
5 hours ago
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The Donner Party begs to differ
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jerlam
5 hours ago
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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).
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mcfedr
1 hour ago
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yes only writes y, not the whole word yes
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fnord77
1 hour ago
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unless you type

      yes yes
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splittydev
6 hours ago
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Alternatively, you could try compiling an Xcode project. That should do the trick as well.
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kristianp
6 hours ago
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Or you could get a laptop that doesn't have an metal shell, like a thinkpad.
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Cassell
6 hours ago
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they often have a magnesium bottom shell
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daneel_w
7 hours ago
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  while true; do openssl speed ecdsap384 -multi 2; done
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mark242
7 hours ago
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npm install
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villgax
34 minutes ago
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This is now running Cyberpunk or an LLM locally
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Scubabear68
9 hours ago
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Needs 2019 in title, this is Intel MacBooks not Apple Silicon.
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dunham
7 hours ago
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I've found that Baldur's Gate 3 will warm up my apple silicon (everyday tasks do not).
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Analemma_
6 hours ago
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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.
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dangus
6 hours ago
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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.

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moralestapia
9 hours ago
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Won't work on M processors, (un)fortunately.
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dajonker
8 hours ago
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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).
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amluto
7 hours ago
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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.)

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asdff
5 hours ago
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I get them going full blast in 2 minutes from cities skylines.
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woozlewuzzle
6 hours ago
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You could also build Chromium from source. It makes my M1 Max's fans sing.
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tom_
5 hours ago
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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!
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asdff
5 hours ago
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Try increasing to 10 cores. Works on my m3 pro.
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mjmas
9 hours ago
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nullbyte
9 hours ago
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sanest emacs user
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RAZKOM
9 hours ago
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There really is an xkcd for everything
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therein
9 hours ago
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Honestly m1 was very cool no matter what workload you threw at it but at this point m4 max does get pretty hot even with just web browsing.
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gpm
9 hours ago
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I've definitely had my m1 air get uncomfortably hot to touch - particularly right above the keyboard. (While doing developery things)
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inventor7777
5 hours ago
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Can't say I've ever thought of a word like "developery", but now that I've seen it I like it a lot :-)
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1e1a
9 hours ago
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Another (more useful) option is to render an animation in Blender, or run a local LLM.
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ale
9 hours ago
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Honestly i prefer my macbook frosty
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