Raspberry Pi 4 Passive Cooling – Is It Worth It?

Since the release of the Raspberry Pi 4 in July 2019, I’m using and recommending the same case (see here)
It was almost the only case available at the release date, and I know that I needed a fan for this new model

What is the problem with a fan cooling system?
That makes noise!
I often have the Raspberry Pi and my computer on the same table when writing on this blog
And I realized that I tend to prefer using the Raspberry Pi 3B+ when possible

It’s even worse if you want to keep it on all day or use it as a media-center device
The Raspberry Pi Foundation has improved the thermal issue, but it’s not yet perfect

So, my goal was to find another solution, without fan if possible, to see if it can work for me
And also to share with you the results I got with it
Let’s go!

Passive cooling introduction

What is passive cooling?

Passive cooling is a common solution to keep the computer parts cool without a fan
Generally, it works with a metal piece placed on the CPU or GPU to dissipate the heat (heat sinks)

In a desktop computer it looks like this:

On Raspberry Pi, there are several solutions that we’ll see in the following

Is it efficient?

Generally, passive cooling works pretty well on entry-level processors, if you don’t ask too much
In my last desktop computer, I had a complete passive solution to cool it, and it was working perfectly
The only limit was if I was playing a few hours, the system could not stay at an optimal temperature

So, it highly depends on the hardware performance and what you do with it
I’m pretty confident that the Raspberry Pi 4 can work without fan for almost anything, but we’ll see that in this review 🙂

Solutions

On Raspberry Pi, there are four main ways to keep the system cool:

• By only using small heat sinks on some components
• Having a passive cooling case, as we’ll see in this post
• By using a passive case + a fan (in case of overheating)
• Or by having only fans to cool everything

I already have dedicated posts on almost every solution, so I’ll be short here

For heat sinks, you can read my tutorial on how to install them here
For the moment, the post is for Raspberry Pi 3B+, but it’s the same process for any model
It’s working well for Raspberry Pi 3B+ but it may not be enough for the most recent models

For the active cooling solution, you can read my Ice Tower review here, where I also make a review of my current case in comparison
The Ice Tower is probably the best option to keep the Raspberry Pi 4 cool whatever happens (if the slight noise is not a problem)

And for the passive cooling solution, we’ll test it right now
I will also give you a link to the passive+fan case alternative

Passive cooling solutions

Available products

You can find many solutions on the Internet for passive cooling on Raspberry Pi 4
As the device heat was the main issue on its release, many manufactures had work on this to offer the best product (passive, active and giant fans)

I have read many good reviews about the Flirc Case and the Argon Neo if you want to give a try (links to Amazon)
But unfortunately, they were not directly available in my country
So, I decided to try another one

Update: I now have ordered and tested both of them. You can read my reviews about the Flirc Case and the Argon Neo by clicking on the links. Both are good, I give you the results of my tests in these articles.

My choice

My final choice was on the Geekworm metal case on Amazon
This product use two aluminum plates to cool the Raspberry Pi (above and below the board)
And the good news is that the GPIO stay accessible without opening or removing the case (unlike the Flirc and Argon solutions)

Same thing for others ports like the camera slot
You can even extend the GPIO pins to use a HAT without removing the case

On the paper this product seems perfect and I’m impatient to see how it works during a stress test

Product review

Package & installation

The package contains everything you need:

• Two passive plates
• 2x GPIO extenders
• 3x thermal tapes
• 4x screws
• A Torx wrench to assemble everything

A paper manual is included, but the installation is intuitive:

• Take your Raspberry Pi and the three thermal tapes
  
• Put them on each corresponding component
  
  It doesn’t stick very well, but it’s enough to do the job
• Place your Raspberry Pi on the bottom case cover
• Then, put the top case cover on it
• And finally install the 4 screws

That’s it, your passive case is ready to use

Review procedure

I will use the same test protocol as in my Ice Tower review, so you can compare the results with my current case and the Ice Tower:

1. Keeping the Raspberry Pi off for 15min
2. Booting the Raspberry Pi with Raspbian Desktop (full version)
   Nothing running
3. Starting a script for the experiment, as soon as possible after the boot
   The test is running during 3 minutes with all CPU at 100%
4. Taking note of the results (temperature) and share them with you

Results

Reminder

Before looking at the results and graphic, let’s do a quick reminder about the expectations we might have
As I told you previously, I have already made this kind of test of the past

Here is what I got:

• No cooling system: The idle temperature is about 45 °C and increase quickly to 70 °C after a 3 minutes stress
• Heat sinks: Almost the same results, with 2 to 5 degrees under the previous value
• Basic fan: Idle temperature near 35 °C, and the maximum stay under 60 °C
• Ice tower: Always under 40 °C

My expectations here are to get almost the same result as with a fan
So, I could keep the case as my primary one, and enjoy a silent operation

Let’s see what happens 🙂

Results

Ok, so there is only one result on this graph
Degrees Celsius on the Y-axis, and time in seconds in the X-axis

Wow!
This passive case results are very close from those I got with the ICE Tower
This is way beyond my expectations 🙂

The temperature stays under 45 °C during all the test, with an idle temperature as low as 31 °C
After 3 minutes, the temperature increase slowly to reach 50 °C after 5 minutes.
I didn’t let it run longer, but if you have a permanent load on your Pi, it’s maybe not the best option (or choose the fan alternative below)

Note: I’m not sure if we can compare these results with the passive case results, as there has been the Raspbian “thermal” update between the two reviews. I didn’t test everything again, but I only get a 5 °C difference without fan. So, these results in themselves are excellent

Where to buy it?

As often, I bought mine on Amazon, so you can probably do the same thing
The case is pretty cheap (close to other basic models)
You can check the price here on Amazon.

On the same page there is an alternative with fans if the passive case is not enough for you
Here is the direct link to it

Let me know in the community if you have tried it and have other opinions

Conclusion

That’s it, this is the end of this review, I hope you enjoyed it
In summary, this passive case is perfect to cool the Raspberry Pi 4, and I will keep it as my default case now
If you use your Pi as a retro-gaming console or as a media center, you’ll love it

If you are looking for other reviews, leave a comment in the community with the stuff you are looking for, and I will see if I can test it in a next post. For now, you can already check these tests:

• Raspberry Pi 4 Cooling: Seeed Studio ICE Tower Review
• Flirc Case Review: Is it Really the Best? (6 Months Usage)
• Argon NEO: Honest Review After 1 Month Usage