
Cooling off your Raspberry Pi 4 - alexellisuk
https://blog.alexellis.io/cooling-off-your-rpi4/
======
schappim
Disclaimer: I work for a company that owns a Raspberry Pi Approved Reseller.

We spend a ridiculous amount of money testing various cases from China. In
testing we found that the heat sink style[1] cases with fan work best.

Having said that, for most use cases you just need to move the hot layer of
air away from the SoC, so even a low speed fan will do the trick.

[1] [https://raspberry.piaustralia.com.au/collections/cases-
enclo...](https://raspberry.piaustralia.com.au/collections/cases-
enclosures/products/armour-case-with-dual-cooling-fan-for-raspberry-pi)

~~~
phkahler
Is it possible that a taller case with vents at bottom and top, plus a decent
heat sink might provide enough convection to go fanless?

~~~
schappim
Certainly, the key is hot air needs to be able to get away from the SoC.

For my home lab, I don't bother with the fans/cases and instead just stack the
Pis with brass spacers.

I haven't had any issues yet with the ambient room temperature around 20-22ºC
(68-71.6ºF for the stonecutters who keep the metric system down[1]).

[1]
[https://www.youtube.com/watch?v=_ZI_aEalijE](https://www.youtube.com/watch?v=_ZI_aEalijE)

~~~
colechristensen
Have you checked if the CPUs are throttling at load?

~~~
bitwize
I use a Pimoroni case with an open bit where the CPU and various other chips
are. I also have a small heatsink on the CPU.

The machine doesn't throttle under load even when I hammer it with a
compilation job on all four cores.

------
lordnacho
Here's a fun thing I just did with my RPI4. I've got "watch -n 1 vcgencmd
measure_temp" running.

Equilibrium temp is arount 73C running a realtime website. Take a £2 coin and
place it on the CPU. Temp drops 10C within seconds. I can get it under 60C by
swapping a second coin. They stay pretty hot after you take them off. Also the
equilibrium temp when you just leave the coin there seems to be a good few
degrees less than with no coin. Possible the larger surface area helps remove
the heat, just not as good as an actually designed heatsink.

~~~
bArray
I think that's called "throwing money at the problem"!

Taping the coin (or heat sink) down should give you better heat transfer,
therefore better cooling.

Designing your own case in OpenSCAD and 3D printing is a piece of cake,
building a large fan into the case (lower noise) is a nice weekend project.

~~~
jagged-chisel
A bit of thermal paste between the chip and the coin would also help with heat
transfer

~~~
lostlogin
Paste between coins with a stacking arrangement going big-small-big-small etc
so that there was a semblance of fins would be interesting.

------
FullyFunctional
I have tried many options (including powerful fans), but the Flirc case [1]
(whole-case passive heat sink) is my favority so far and cools well enough for
a 1.75 GHz overclock under torture testing (2+ GHz would crash under torture).
[1] [https://flirc.tv/more/raspberry-
pi-4-case](https://flirc.tv/more/raspberry-pi-4-case) (I'm not affiliated,
just a content customer).

~~~
int_19h
There is an even better take on the whole-case heat sink concept, although it
gets pricey:

[https://wickedaluminum.com/products/raspberry-
pi-4-standard-...](https://wickedaluminum.com/products/raspberry-
pi-4-standard-case-with-heat-dissipation)

~~~
blacksmith_tb
Might as well go all the way to AstroPi[1] at that rate. Though I wonder if
Flir couldn't make a copper-top version for less money than either, really...

1: [https://makezine.com/2015/12/01/raspberry-pi-
iss/](https://makezine.com/2015/12/01/raspberry-pi-iss/)

~~~
FullyFunctional
In which way is this "all" more than the flirc case? The Flirc case makes
physical contact with the CPU and radiates heat all over the case. Don't let
the black (removable) plastic top fool you - it's one solid piece the whole
way.

~~~
blacksmith_tb
I didn't meant the Flirc case so much as the machined, high-dollar one. The
Flirc one looks great, esp. for $15.

------
mrlambchop
Having recently built a picade with a Pi4 and ran it in a cool room for around
2 hours, the device kept crashing when playing various emulators. After the
final crash, it didn't start up again. Opening up the back was like opening
the door to an oven and the Pi4 was just steaming. Nothing was obviously
melted, but it didn't work again :(

~~~
darkmighty
This seems conflicting with what I read about its behavior. It should heavily
throttle (underclock) itself, but shouldn't destroy itself. Maybe you got a
defective unit or the hot thermal environments caused issues elsewhere (again
maybe due to some defect).

~~~
colechristensen
I had a power supply with similar problems which actually started on fire - I
had been restarting it repeatedly after it kept (supposably) hitting thermal
or some other shutdown condition.

Lesson: just because there are protections for going past limits doesn't mean
that everything is fine when you are constantly hitting them. (applicable to
our current government problems sadly)

------
jascii
"The heat will be spread out, but not moved away from the device, so once it's
hot, it will likely radiate that heat around the board." The author doesn't
seem to grasp the concept of convective cooling or how heatsinks are supposed
to work.

~~~
GhostVII
I think that comment was in contrast to what they said about the fan:

> This option does apply a decent amount of cooling at idle and under load, it
> also moves the heat away from the board unlike the heatsink.

I think the comment makes sense with that context, compared to a fan, the heat
from a heatsink will stay near the board and make future cooling less
efficient.

~~~
OJFord
But with or without a fan, the point of a heatsink is to increase surface area
for convection.

A fan also aids convection, but instead by maintaining a larger temperature
difference between the surface (however large) and the surrounding air.

Either alone is good; both together are better.

------
MaXtreeM
The article is basically just a list of some options. Even for the most
advanced option the author writes just about temperautures in "mostly idle"
setup. Anyone has a link to an article with actual measurements?

~~~
ageofwant
Here's a nice summary video as well
[https://www.youtube.com/watch?v=qa3YnWhzPsw](https://www.youtube.com/watch?v=qa3YnWhzPsw)

~~~
read_if_gay_
Another:

[https://youtu.be/AVfvhEJ9XD0](https://youtu.be/AVfvhEJ9XD0)

------
AceJohnny2
So many ad-hoc solutions, but I can't seem to find the maximum power
consumption/TDP of the RasPi4, which would inform the kind of dissipation
you'd need.

Best I could find was the BCM2711 (the Broadcom SoC at the heart of the
RasPi4) "datasheet" (a frickin' _Word document_ ) [1] that says the board
requires a PSU capable of providing 3A at 5V.

So that'd be 15W.

[1]
[https://www.raspberrypi.org/documentation/hardware/raspberry...](https://www.raspberrypi.org/documentation/hardware/raspberrypi/bcm2711/rpi_DATA_2711_1p0_preliminary.pdf)

~~~
fivesixzero
RPi power consumption and power supply is a bit more complicated than it seems
on the surface.

A large problem is that even “3A rated" supplies suffer large voltage droop
under load. This can be seen pretty easily using a cheap USB DC load [0]. As
load goes up, voltage tends to drop slowly at first, then heavily at a certain
point.

Several I’ve bought drop as low as 4.1V at just 2A load which will almost
definitely make any Pi very unhappy. I haven’t found an authoritative source
but generally the Pi’s power management system starts complaining (flipping
the “undervolt since boot” bitflag [1] in “vcgencmd get_throttled”) around
4.6-4.7V [2]

To monitor the throttled bitflags, which also report thermal throttling, I
wrote a basic shell script that just converts the hex to bin then returns a
Grok-ready string with the flags as booleans. I've already got Telegraf on the
RPis sending basic host metrics to an InfluxDB instance so that script just
gets called by an exec input to generate and persist the data for monitoring
or analysis.

Eventually I'd love to write (or contribute to) a proper Golang Telegraf plug-
in that just reads from the VC mailbox directly but that's still on the back
burner.

As far as actual power consumption during use, I’ve recently started running
tests using a decent USB power meter (WITRN/Qway U2 [3] and X models, in
particular) to monitor load over time while running various workloads on a Pi
Zero W, a Pi 3B+ and a 4GB Pi 4.

Power usage at idle is usually low but even that's unpredictable. Daemons are
gonna daemon regardless of the user load. Generally though the load goes up
substantially when powering peripherals - Ethernet, USB, BCM VideoCore
enc/dec/CSI/SSI, SD card R/W, HDMI, fans, HATs, GPIO peripherals, etc. CPU
load definitely factors in heavily, of course, but it’s only part of the
picture.

For reducing power usage, some surprisingly simple things can help. As a very
minor example, shutting off the activity LED [4] can save a few dozen mA. :)

[0] [https://www.droking.com/Intelligent-USB-Adjustable-
Constant-...](https://www.droking.com/Intelligent-USB-Adjustable-Constant-
Current-Electronic-Load-DC3-21V-3.5A-35W-Mobile-Power-Detector-Tester-USB-
Discharge-Resistance)

[1]
[https://raspberrypi.stackexchange.com/questions/48329/underv...](https://raspberrypi.stackexchange.com/questions/48329/undervoltage-
warning-despite-decent-power-supply/48337#48337)

[2]
[https://www.raspberrypi.org/forums/viewtopic.php?f=63&t=1477...](https://www.raspberrypi.org/forums/viewtopic.php?f=63&t=147781&start=50#p972790)

[3]
[https://usbchargingblog.wordpress.com/2018/08/11/web-u2-usb-...](https://usbchargingblog.wordpress.com/2018/08/11/web-u2-usb-
meter-monitor-upm-quick-look/)

[4] [https://www.jeffgeerling.com/blogs/jeff-
geerling/controlling...](https://www.jeffgeerling.com/blogs/jeff-
geerling/controlling-pwr-act-leds-raspberry-pi)

~~~
rasz
>drop as low as 4.1V at just 2A

the whole point of a 3A rated 5V power supply is it will not drop more than
~5% under its rated load. What you describe is being a victim of a fraud.

~~~
michaelt
According to [1] a 1 meter USB cable can have a resistance of 286 milliohms,
for a voltage drop of 0.8v over a meter (taking the resistance of four
contacts and two lengths of cable into account).

So if you have a '3A 5V' power supply without a captive cable, you can still
get 4.1v at the useful end of the USB cable.

The official RPi chargers include a captive cable, presumably to stop users
substituting such standard USB cables.

[1] [https://www.westfloridacomponents.com/blog/compensate-
cable-...](https://www.westfloridacomponents.com/blog/compensate-cable-
voltage-droops/)

~~~
imtringued
The raspberry pi sells power supplies not chargers

------
emmelaich
geeky nitpick -- do not use `while [ true ]; do ..`

It's not doing what you think; `true` here is just a non-zero length string.
`while [ false ]; do ..` does the exact same thing!

Use `while true; do ...`. Or better `while :; do ...`

Even better, depending on the context, is

    
    
       while sudo sudo /opt/vc/bin/vcgencmd measure_temp; do
         sleep 2
       done
    

PS. why two sudos?

------
jrockway
I got a 5V Noctua fan and use this enclosure:
[https://www.thingiverse.com/thing:3723481](https://www.thingiverse.com/thing:3723481)

Seems to stay very cool and is silent. Noctua makes some good fans.

~~~
StavrosK
It needs a 5V fan, right? You power it from the GPIO pins directly?

~~~
jrockway
Yeah, exactly.

------
tpmx
I guess Raspberry Pi 3 B+ (or CM3+) was close to the sweetspot in terms of
thermal management vs performance tradeoffs, for many applications. Unless you
really need more RAM or higher USB speed.

I hope the next two main steps for the next Raspberry Pi (4+ or 5?) and the
corresponding compute module will be:

a) including a SATA controller (SD cards are not... ideal.)

b) a more power-efficent node

~~~
sorenjan
I don't think a SATA controller makes sense for them. Keeping the price low is
an important design goal, and adding more chips goes against that. An external
hard drive with USB3 is probably the best option for a while.

~~~
tpmx
I'd start looking at _actual_ volume prices for controller chips first, before
dismisssing this, but that's just me. I have no idea what the cost is, but I
could imagine it to be like maybe 5-10 cents by now. Just a guess. It's that
kind of old but still very useful tech by now.

~~~
nlfwhulsdhouv
Nothing of that complexity is 5-10c in volume (even huge volumes). I would
guess somewhere in the 1-2$ range, which _is_ a big issue for them. For
reference, 5-10c won't even buy you a middle to low performance op-amp.

The Pi became possible because of integration, where the SoC supported all the
required interfaces internally so very few external ICs were required. That's
what allows them to keep the price so low. Additional chips add significant
additional cost. That's why there have always been compromises like the USB-
connected ethernet. They can only do what the SoC supports natively.

~~~
tpmx
_Exactly how_ certain are you of this?

Keep in mind that this is a 10+ year old problem by now (talking about
USB2-to-SATA). They've gone through all of the cost cutting methods possible
by now.

I can buy that chip that also happens to come with a PCB, a very nice extruded
and anodized alumunium case, plastic end-pieces + screws, indication LEDs,
voltage regulators, 10-20 pieces of small passives (redistors/caps), a
screwdriver, 2-3 pieces of instrution manuals/warranty notices, two layers of
very nicely designed paper packaging + shrinkwrap... all for like $5 in
retail. The cost to the retail store for these items is probably closer to $2.

(Oh, and there's also the assembly cost for that PCB inside the case.)

~~~
nlfwhulsdhouv
> Exactly how certain are you of this?

This is my job. I design consumer electronics that ship in volumes larger than
the raspberry pi. You've probably used something I've designed before. The
backseat engineering by software devs in these threads is annoying and
presumptuous. The pi designers aren't incompetent, they've probably rolled up
dozens of feature BOMs to find what they can afford to ship.

Now, I wouldn't be surprised if it was 50c instead of 1$, but _nothing_ is
5-10c, so you're off by an order of magnitude. Even a single transistor in a
package is a few cents. Additionally, if they add the IC they still need a
connector, and those are some of the more expensive components in a device
like the pi, probably 25c-1$ depending on quality.

> I can buy that chip that also happens to come with a PCB...

You're right that the economics don't seem to make sense, but you made several
mistaken assumptions:

1) The price of that device is _almost entirely_ driven by the cost of the IC.
Those designs have almost no supporting electronics, and the PCB itself will
be 10-20c.

2) You're overestimating the margins. It's probably not delivered to the
retailer for 2$, closer to 3$. Generic electronics are not high margin.

3) In cheap, commodity devices the manufacturer can use grey-market ICs, but
the pi designers can't get away with that. That easily doubles the IC price.

~~~
tpmx
> This is my job. I design consumer electronics that ship in volumes larger
> than the raspberry pi. You've probably used something I've designed before.

Fair enough. Thanks for your explanation.

> The pi designers aren't incompetent, they've probably rolled up dozens of
> feature BOMs to find what they can afford to ship.

That's a borderline straw man argument. You're seem to be implying that I
either wrote (or think) that they are incompetent, while none of those things
are true.

> Now, I wouldn't be surprised if it was 50c instead of 1$, but _nothing_ is
> 5-10c, so you're off by an order of magnitude.

Okay, let's say it's 50 cents. I would still think it makes sense to include
this feature. Also, that's "half a magnitude off" compared to 10 cents, not a
magnitude off.

------
esotericn
I have the ICE tower with mad LEDs!

'cos I'm a little boy inside.

Stable 33% overclock, I'm typing to you from it now. :D

    
    
        $ cat /sys/devices/system/cpu/cpu0/cpufreq/cpuinfo_max_freq
        2000000
    

pic: [https://files.esotericnonsense.com/pub/rpi-
tower.jpg](https://files.esotericnonsense.com/pub/rpi-tower.jpg)

~~~
barsonme
Same with the ICE tower and 2GHz overclock.

Even with stress tests I can't get the Pi to break 50 C.

I don't use mine as a desktop yet, though. I just run 8 Docker containers for
stuff like DNS, Time Machine backup, etc.

The goofy-looking Pi:
[https://www.ericlagergren.com/share/d9htGfiETJHN3ua](https://www.ericlagergren.com/share/d9htGfiETJHN3ua)

~~~
esotericn
Hehe. Yours is a little cutie too!

I've just borked my install trying to migrate to aarch64 from armv7h.

Currently rescuing it (I hope) with a chroot.

Fun! :D

edit: all sorted! aarch64 kernel compiled; migrated the userland over from
armv7h (I've been using 32-bit for a few months) - no issues so far! whee!

~~~
barsonme
Good luck! I'd like to hear how Arch works out for you. I used to use Arch
before I switched to macOS. If I ever get around to using a Pi as a desktop,
Arch will definitely my first choice.

~~~
jsjohnst
GP is not talking about the Arch Linux distro, but rather switching to using a
distro compiled for the 64 bit ARMv8 ISA. It’s not a completely accurate
comparison, but a fair analogy is armv7h is to aarch64 as i386 is to x86_64.

~~~
esotericn
I was in fact talking about Arch (though the 'unofficial' ARM port;
[https://archlinuxarm.org](https://archlinuxarm.org))

Though I believe barsonme picked that up from my other post below.

~~~
jsjohnst
Heh! My bad then. Was going off the post replied too and assumed (this is what
I get for assuming!) they wrongly read aarch64 as Arch.

------
gatherhunterer
I just put my stack of Pis in front of a Noctua NF-S12A and it cools them all
very effectively, even under heavy load, without the need for any goofy
hardware that blocks additions like the GPIO extender or any other HATs I may
want to add. I bought an adapter to power it from one of the Pis. It’s an easy
solution that works for many of them with negligible effort.

------
bproven
I have one of these cases[1] for my Pi4 4GB from Amazon. Comes with heatsink
and small fan (very quiet). Right now running "watch -n 1 vcgencmd
measure_temp" puts it at 36C idle. Well I guess it is actually running k3s
with no deployments/pods, so fairly idle.

I do remember it running a bit hotter before I updated to the latest firmware
via "sudo apt full-upgrade" a few days ago.

Running "stress -c 4" gets it up to about 50C ...

[1] [https://www.amazon.com/Raspberry-iUniker-Heatsink-Model-
Sing...](https://www.amazon.com/Raspberry-iUniker-Heatsink-Model-
Single/dp/B01LXSMY1N?ref_=ast_bbp_dp)

------
ChuckMcM
I've got three 4GB pi4's running. Two are in FLIRC cases which do an Okay job
(and they look good :-) They transfer heat to the case and the Pi peaks out on
my loads at about 55C. I've also got a cheap fan+heatsink solution
([https://www.amazon.com/gp/product/B07TZQHXZ6/](https://www.amazon.com/gp/product/B07TZQHXZ6/))
which does a better job and keeps the Pi under 50C on all loads (it doesn't
throttle at all).

------
fivesixzero
I recently put my Telegraf configs/scripts for monitoring RPi thermals and
throttling into a git repo. These might be helpful for anyone doing their own
comparative testing of cooling soliutions and/or power sources.

[https://github.com/fivesixzero/telegraf-pi-
bash](https://github.com/fivesixzero/telegraf-pi-bash)

------
yellowapple
Has anyone tried immersion cooling (i.e. submerging an RPi in mineral oil)?
Tempted to try it myself; just need some spare time (that I don't squander by
commenting on Hacker News ;) ).

~~~
Sendotsh
Yes it has been done, and works[0-3], it's just a matter of effort vs reward.
Generally a simple heat sink and/or small fan setup works fine for nearly any
usecase the Pi is designed for, and if you really do need to do heavier loads
that require that level of effort to cool, then you probably shouldn't be
using a Pi in the first place.

[0]
[https://www.youtube.com/watch?v=yJRrGCqG9Jc](https://www.youtube.com/watch?v=yJRrGCqG9Jc)

[1] [https://hackaday.com/2018/08/13/oil-immersed-raspberry-pi-
ke...](https://hackaday.com/2018/08/13/oil-immersed-raspberry-pi-keeps-its-
cool-under-heavy-loads/)

[2] [https://hackaday.com/2017/05/15/liquid-cooling-
overclocked-r...](https://hackaday.com/2017/05/15/liquid-cooling-overclocked-
raspberry-pi-with-style/)

[3]
[https://www.reddit.com/r/raspberry_pi/comments/bmeklj/pi_imm...](https://www.reddit.com/r/raspberry_pi/comments/bmeklj/pi_immersion_cooling/)

If it's just for fun, then I think water-cooling Pi's looks way more
interesting to play with:

[http://finniss.net/water-cooled-raspberry-pi/](http://finniss.net/water-
cooled-raspberry-pi/)

[https://modmymods.com/modmymods-raspberry-pi-mini-water-
cool...](https://modmymods.com/modmymods-raspberry-pi-mini-water-cooling-kit-
mod-0171.html)

------
205guy
I'm no expert, but one of the blogs I read had detailed posts about putting a
heatsink and fan on a RPi3B+ and using it as a desktop and dev machine:

[https://syonyk.blogspot.com/2018/09/raspberry-pi-3b-flirc-
ca...](https://syonyk.blogspot.com/2018/09/raspberry-pi-3b-flirc-case-
thermals-and.html)

[https://syonyk.blogspot.com/2018/09/project-pi3bdesk-
making-...](https://syonyk.blogspot.com/2018/09/project-pi3bdesk-making-even-
better.html)

------
StillBored
Outside of maybe the ICE cooling tower I suspect that all of these
heatsink/fan solutions are woefully under specified if you happen to load the
system or overclock.

I grabbed one of my little 20mmx20mm heatsinks which are generally good enough
for devices of that size that come passively cooled. In the RPi's case that
thing got hot enough to burn me even with a small fan. So I repeated this
process a few times with stuff from my junk box trying to find a passive
solution eventually I ended up with a 40x40x30mm heatsink (looks sorta like
this [https://www.amazon.com/Karcy-Aluminum-Heatsink-Cooling-
Raspb...](https://www.amazon.com/Karcy-Aluminum-Heatsink-Cooling-
Raspberry/dp/B07QQSQDXF/ref=sr_1_42?keywords=40x40mm+heatsink&qid=1573861603&sr=8-42)
only that one says its 11mm) and a small fan.

The thing is huge, but the temps stay under control and it over-clocks @2Ghz
now, but I wouldn't run it like that for long even with that heatsink. I've
got mine pinned at 1.75).

------
derekp7
One of my disappointments with the Pi 4 is that the official case for it got
rid of any ventilation. Previous cases had vents and a removable top plate.
I've found that the Primori fan shim works really good, but only with the
cover removed. Will have to try drilling some vent holes in the cover and the
back side of the case, and see if I can make it look good.

------
tmikaeld
A model, temperature, noise, price - summary table would have been nice.

~~~
kingosticks
And size, that ice tower thing is huge. I'd prefer the heat sink case, which
I've anecdotally heard does a great job.

------
m4r35n357
+1 for the heatsink case! [yes I have one]

~~~
aelo
I also bought this one because I wanted a passive solution. Temperature looks
fine (45°C in Idle). Although I think there are different versions and some of
them don't fit perfectly on the RPi4. I got mine from amazon and it cools the
three most important chips but the position where it touches the chips isn't
perfect.

------
bakul
Note that the main issue here is to avoid cpu throttling due to excessive
heat. IIRC you can allow a higher cut-off temp (100ºC instead 77ºC) by setting
a config parameter. This will possibly reduce the chip lifespan from whatever
it is to _decades_! But make sure no one can accidentally touch the chip.

I have one case with a fan and one case where part of the case body attaches
to the chip top with thermal goop. The fan works better.

------
ksaj
I read about the heat issues, so when I bought my pi4 I also got an aluminum
fin cooler case with 2 fans built into it. Thankfully the fans are totally
silent. I half expected it to sound like half a drone.

Now I can crank it up and rip the knob off, and the temperature doesn't get
anywhere near throttle point.

------
ImprovedSilence
I have the fan shin on mine, set it up so it clicks over a certain temp, and
it’s been working great for me.

------
lightedman
Why do companies insist on shipping something that otensibly requires a heat
sink, without the heat sink itself?

If I shipped out a fully-powered MK-R LED without a heat sink, saying "Oh
it'll work fine!" I'd be getting chewed out within two minutes of the customer
turning it on.

~~~
Erlich_Bachman
Maybe for the same reason that you can by a CPU without a heatsink - in order
to provide flexibility. They assume that the number of people that will want
to specialize and customize their heatsinks/fans will be so high in proportion
to the people that will be just fine using the standard sink, that it is not
worth it. There are very cheap easy to mount (like 2 seconds easy) heatsinks
that will do the job (probably with thermal throttling though).

------
georgeecollins
The problem for me is I attach a card to the top of the Pi for robot
circuitry. That makes putting a heat sink or fan on the board awkward. I feel
like having to do this really compromises the versatility of the Pi. For now I
am sticking to 3s until I hear the temp issue is solved.

~~~
opencl
The Pi 3 has the same thermal throttling issue as the 4, and the 4's
performance under throttled conditions is much higher.

Though IMO even calling it an issue is overblown, most phones and laptops
cannot maintain their peak clocks under load for extended periods of time
either. Intel calls it turbo boost so it's a feature instead of a bug.

~~~
georgeecollins
Really? Because I run a Pi with a servo board on top that gets quite hot (too
hot to touch) and it seems like CPU is performing time sensitive calculations
(walking kinematics) adequately. It could be that the calculations are simple
enough that they are insensitive to the throttling down. Do you have a
suggestion how I could write some Python code to check if the 3 is throttling
down? (Maybe a link to an example?)

Maybe it wouldn't be an issue on the Pi 4 that I think it is. In that case I
have been holding back on switching to a 4 for no good reason. This is very
helpful, thank you.

~~~
sbierwagen
[https://newscrewdriver.com/2018/09/06/detecting-raspberry-
pi...](https://newscrewdriver.com/2018/09/06/detecting-raspberry-pi-thermal-
throttling-from-console/)

~~~
georgeecollins
Sam- thank you for this link. It is very helpful.

------
rafaelm
This video is pretty good, the guy does some testing of different cooling
options:
[https://www.youtube.com/watch?v=vkLr08K0c1E](https://www.youtube.com/watch?v=vkLr08K0c1E)

TL;DW: The Flirc case is one of the best options.

------
robbles
Does running an idle k3s cluster really require adding a heatsink to the rpi?

I would have thought this would generate very little load, and a major temp
increase might indicate a bug in k3s?

Is there a bunch of cpu-intensive work an idle cluster needs to do?

------
hinkley
There’s something to be said for having the cpu on the back side of the board,
like some of the NanoPi models. Easier to spread the heat with no connectors
in the way.

------
cocoa19
I wish all fans use the pi temperature sensor to regulate speed. I got one
with the CanaKit and it doesn't.

My OCD kicks in when I can hear the fan running all day long.

------
echelon
What was the last version of Raspberry Pi that didn't require cooling?

What's the best-spec'd Pi (or comparable alternative) that doesn't require
fans?

~~~
darkmighty
Most don't _require_ cooling, but will have better clocks. The 4 itself
throttles under heat (above 60C and heavily over 80C), and seems to have good
enough behavior even if not actively cooled.

------
Adiqq
I'm not sure why, but my RPI4 become broken 4 times in a row. I returned it 3
times, but finally I gave up. Every time it eventually stopped to boot up and
there was solid green and red LED light. There was original raspberry PI case,
modified to mount Noctua 5V fan, with additional holes to allow air
circulation. There was original power supply. It was only connected with
ethernet, this fan through GPIO and HDD drive through USB.

Now I have HP T620, can be bought cheaply, it's definitely bigger than RPI4,
but finally it just works.

------
freeflight
I wonder why PC cooling brands haven't discovered this market yet.

Building a heat sink case with attachable fans doesn't seem all that
impossible.

------
luc_
Yes, I know what a heatsink is and how to google for heatsinks for a RPi.
TYVM.

