
Way to keep your cool running a Raspberry Pi 4 (2019) - guiambros
https://www.jeffgeerling.com/blog/2019/best-way-keep-your-cool-running-raspberry-pi-4
======
tosh
vertical orientation also seems to impact temperature

""" Simply moving Raspberry Pi 4 into a vertical orientation has an immediate
impact: the SoC idles around 2°C lower than the previous best and heats a lot
more slowly – allowing it to run the synthetic workload for longer without
throttling and maintain a dramatically improved average clock speed.

There are several factors at work: having the components oriented vertically
improves convection, allowing the surrounding air to draw the heat away more
quickly, while lifting the rear of the board from a heat-insulating desk
surface dramatically increases the available surface area for cooling. """

[https://www.raspberrypi.org/blog/thermal-testing-
raspberry-p...](https://www.raspberrypi.org/blog/thermal-testing-raspberry-
pi-4/)

~~~
jacquesm
It's not that simple in the general case though: putting a board vertical will
cause the top of the board to be hotter than the bottom, possibly a lot hotter
than it would have been in a horizontal position even if the average
temperature of the board is a lower one!

Looking through a thermal imaging camera gives all kinds of interesting
insights.

------
rc4hobby
Thermal engineer here. There absolutely no need to use fan cooling, humongous
heatsinks or harebrained temperature controller schemes to cool the raspberry
pi 4.

All that is needed is a small heatsink to slightly decrease the thermal
resistance to ambient air, to stay below the thermal throttling threshold.

Anything more complicated than that is a pointless exercise in pointlessness.

~~~
Arnt
Would you describe that flirc case as complicated? To a naïve layman, it seems
like the smallest all-metal case that'll fit the rpi4, made so that the metal
acts as a heatsink. Which may be more heatsink area than a 15W CPU needs, but
not bigger case area than is needed. Is there something I'm missing?

~~~
smichel17
I got a pi 4 around 6 months ago and got the flirc case based on the
recommendation of TFA. I've been very pleased with it - makes the pi look
nice; I no longer worry about other people touching it; and of course it cools
well (the very thick thermal pad connecting to the case is a bit unusual, but
it works).

I got the flirc usb dongle for remotes at the same time, since I thought I'd
want it (my pi is a media center) and there was a discount at the time if you
bought both it and the case.. I've been far less impressed. It's a great idea
in theory, but in my experience there was enough flakiness/delay with each
button press, especially with Kodi for some reason, that it was basically
unusable. Also, their utility for programming the dongle did not run well on
the pi itself (it stores configuration on-device so you don't need to program
it from the device you'll be using it on), and the install process involved
setting up a repo that is served over http and does not have an associated gpg
key, which gave me a bad feeling (although overall it felt more like a startup
flying by the rest of its pants than anything malicious). I am somewhat
hopeful that with more time/polish these issues will be fixed in software, but
can't currently recommend it.

~~~
ja27
Kinda wish the top of the FLIRC case wasn't rubberized. My older one is sticky
now, but that might be more of an issue in Florida humidity. Still got one for
a Pi 4 and it ran well enough.

------
vardump
The article is dated November 22, 2019, which makes me wonder whether it was
_before_ the Raspberry Pi 4 firmware upgrade that reduced heat generation
quite a bit.

My two 4GB Raspberry Pi 4s have had no thermal issues. Running the same
measurement script now, will report back the results.

Edit: Ok, done with the tests. Both RPi4s are bare and should be running
exactly the same versions.

RPi4 #1 started at 51C, peak 79C, no throttling at any point. Ambient
temperature 24C.

RPi4 #2 started at 54C, peak 82C at which point it started to throttle.
Ambient temperature 27C.

~~~
kingosticks
Are you talking about the update described at
[https://www.jeffgeerling.com/blog/2019/raspberry-
pi-4-might-...](https://www.jeffgeerling.com/blog/2019/raspberry-pi-4-might-
not-need-fan-anymore) which is mentioned in the article? Or something else?

~~~
vardump
Possibly.

I haven't closely followed RPi4 firmware development, but I did notice
positive changes since June 2019. I think there have been at least two
occasions that dropped the (idle) operating temperatures.

In any case, I'm happy with their thermal performance.

~~~
kingosticks
I've also a feeling there were two things they changed but I don't recall what
the first one was. And I don't think there's been any more improvements since
November so I think this article includes everything so far.

When the pi 4 first came out, mine throttled when driving two screens and that
was depressing. I've not tried that setup again since but I really should.

------
herogreen
Nice test, it could be cool to have people repeating it to see how much the
"silicon lotery" influences the temps.

Also there a few model of cases on ebay/aliexpress that would be interesting
to test such as
[https://m.aliexpress.com/item/4000509636456.html](https://m.aliexpress.com/item/4000509636456.html)
(with a heatsink added)

~~~
philliphaydon
I have one of these:

[https://cdn-shop.adafruit.com/1200x900/4340-08.jpg](https://cdn-
shop.adafruit.com/1200x900/4340-08.jpg)

It never gets hot that I can't touch it.

[https://www.aliexpress.com/item/4000392602236.html](https://www.aliexpress.com/item/4000392602236.html)

------
reitanqild
Anyone has links to similar articles with regards to either

\- SD card reliability

\- techniques for reliably using what we have

?

Given that people are using these for all kinds of stuff there must be some
advanced techniques being used (or some basic I have missed).

~~~
lis
I've been running a raspberry 3 with a cheap sandisk sd card for years now
without any SD Card issues. It runs a DNS based ad-blocker and a vpn.

I am logging everything to ram instead of writing it to the card and that's
about it. I never encountered any issue with SD Card reliability, despite me
sometimes just pulling the plug instead of properly shutting it down.

Here is a simple guide:
[https://raspberrypi.stackexchange.com/a/62536](https://raspberrypi.stackexchange.com/a/62536)

I do have a couple of other raspberries for other uses (e.g. a small rc car)
which are also running on their first SD card. Might be just luck, but I do
think that it's not necessary to go to extreme lengths to have them run
reliably.

~~~
lloeki
Many problems with SD cards are actually rooted in power issues (bad power
source or usb device that eats power). Ever since I took proper measures to
ensure stable enough power I've had no issue (Pi 3B here)

~~~
avian
> Many problems with SD cards are actually rooted in power issues

Does anyone have any info on this that's more substantial than hearsay?
Experiments, measurements or at least a more technical explanation than "bad
power source"?

I'm persistently hearing this story that power supply quality affects SD card
life. As an electrical engineer, and given what I know about R. Pi design, I
fail to see how an SD card could get physically damaged by any reasonable
power supply that would otherwise run the rest of the R.Pi.

I suspect people are confusing filesystem corruption due to brownouts/OS not
shutting down cleanly with physical damage to the flash (i.e. unreadable
sectors on SD card)

~~~
lloeki
> I'm persistently hearing this story that power supply quality affects SD
> card life

Not SD card _life_ indeed (in my case at least), merely IO failing, hosing the
filesystem long term because of b0rked writes. The SD card is fine, it's just
the data that eventually becomes inconsistent garbage.

I noticed the power LED showed the undervoltage behaviour, measured the power
output which indeed showed the voltage not being stable on power spikes, so
bought a better power supply, problem gone. Got the same kind of issue with
greedy USB devices, so either went the powered hub route or used self-powered
hard disks.

------
m463
The reasonable answer seems to be the flirc case.

No noise, no moving parts, excellent cooling.

------
digitalsushi
Up here in NH it gets a little chilly in the barn loft where the server rack
is hiding inside an old credenza. A chicken egg incubator on a heat switch
keeps the spinny disks on the NAS above 35F and it turns off at 45F. It only
turned on a few times during the coldest days last year. I dont know for a
fact whether spinny disks like to be above freezing but anecdotally someone
said yes and it was 12 bucks to set it up.

~~~
walshemj
When we had some very cold winters in the UK I had to wait for the room to
warm up for our 8 inch floppys to work in our DEC PDP.

------
ohazi
The flirc case is a giant heat capacitor, not a heat sink.

Notice that it has the only temperature curve where the temperature does not
go back to baseline after the stress test. It needs a lot longer to get to
equilibrium, and the final temperature is almost certainly hotter than what's
shown on the graph.

~~~
dannyw
exactly. For passive heat sinks, you need big surface areas. The FLIR case
doesn’t do that and is arguably one of the worst options esp considering its
price.

~~~
zeckalpha
$16?

------
no_gravity
My PI is _too_ cool. It freezes.

I have playing with a PI Zero W over the last weeks. At first everything
worked as expected.

But now it developed some strange "hangings" I cannot explain. It kinda
randomly freezes in time for a few minutes every now and then.

Sometimes it takes several minutes to ssh into it. Sometimes, the terminal
just freezes for several minutes.

Neither top nor iostat seem to show any elevated activity during these
periods. Since they hang throughout the freeze, its a bit hard to say though.

The strangest thing: Pings to the PI always come back fast. So its probably
not that the hardware really freezes completely.

~~~
mszcz
Have you tried replacing the SD card with a fresh one with a fresh install and
checking if this still occurs? I've had a somewhat similar problem and it
turned out to be a dying SD card.

~~~
no_gravity
I will try that. At first I would like to see if I can find the problem. I
would have thought that when the SD card is not responding, it would show up
as "wa" in top and "%util" in iostat -x. But both are zero for the next output
after a freeze.

------
tjpnz
I'm using mine primarily as a streaming device. In my experience a heatsink is
more than good enough. Depending on your workload all a fan will do is make a
bunch of noise and spread dust around.

------
alexellisuk
Folks may also enjoy "Cooling off your Raspberry Pi 4" from my blog (also in
2019) [https://blog.alexellis.io/cooling-off-your-
rpi4/](https://blog.alexellis.io/cooling-off-your-rpi4/)

I compare a number of the different fan / heatsink solutions including
pro/cons along with a hacked Noctua fan

------
umaar
I've been doing voice + screencasting on a modern MacBook Pro. The fans seem
to intermittently kick at full blast while connected to a 4k external display,
or sometimes it's just Dropbox doing CPU intensive things. Either way it's
disruptive to the sound, and background noise removal in post doesn't
completely fix it.

I've never had to think about heat dissipation so much. Might try a laptop
cooling pad.

------
roland35
This is timely for me, I finally am upgrading my original A to a 4! Another
advantage of the Flirc case is that it hides the blinking lights which are so
tempting for my toddler!

------
louwrentius
I’ve tested a heatsink case on a Pi4 with and without fans. Without the fans
at max load (all cores) it didn’t pass 60 degrees Celsius (20C ambient). So
fans are not required.

~~~
teddyc
Same, I hit 59 degC max running the script from tfa. I'm in a house with the
A/C on set to 80 degF.

Edit: this is my case

[https://chicagodist.com/products/black-
raspberrypi-4-armor-a...](https://chicagodist.com/products/black-
raspberrypi-4-armor-aluminum-alloy-cooling-case)

------
ChuckMcM
I have a bunch of the FLIRC cases for my various versions. They are relatively
expensive for what they are but they work well.

------
mseidl
I've had a little fan on an old rpi3 I had and it was annoyingly loud.

------
dannyw
Why do people use cases on a Pi? I’ve never ever used a case.

My Pis are always out of the way and in a shelf somewhere, untouched until I
make modifications to the setup, in which case the case is often coming off
anyway.

~~~
Arnt
So the cleaners will touch the case, not the electronics. Also, the bare board
doesn't offer a convenient way to fix the Pi to a wall IIRC.

~~~
yjftsjthsd-h
> Also, the bare board doesn't offer a convenient way to fix the Pi to a wall
> IIRC.

My Pi 3 has little circular holes that I assume are meant to mount into a
case, but which I have successfully used to just hang the board on a hook on
the wall.

