The new Raspberry Pi 4 is substantially more powerful than previous versions despite sharing the same form factor. However, this increased performance means higher energy consumption and higher heat generation. So, if you want to give your Raspberry active cooling, then we are going to show you how to make a case with a fan so that it always stays at a good temperature.
The Raspberry Pi 4 generates considerably more heat than its predecessors, and without active cooling it suffers thermal throttling even without reaching maximum load and their performance is greatly reduced, so providing the device with some type of extra cooling is almost mandatory. There are many Raspberry Pi cases from manufacturers that include a fan as standard, but if you already have a case for your Raspberry and don’t want to buy another (or if you want to do a bit of DIY), we will tell you how you can make it yourself.
Necessary materials
This is a fairly simple mod that doesn’t require overly expensive tools, and in fact most of you will most likely already have them in your home. In this tutorial we are going to use a Raspberry Pi Model B and its official case as an example, but you can use it with any other Raspberry model and case that you already have as long as it is closed and has space to install the fan.
This is what you will need:
- Electric or Dremel felling.
- Circular saw bit of the appropriate diameter for your fan (30 or 40 mm recommended).
- One 30 / 40mm diameter fan (4V, 2-pin version).
- Four screws for the fan.
- Double-sided tape (recommended, not required).
- A fine file (or drill / Dremel file bit).
You can buy if you want a kit that already comes with a specific fan for Raspberry Pi with its hardware, which is quite cheap.
Install the fan on the Raspberry Pi
The first thing you should do is decide what size you want the fan (the 40 mm one will push more air at a lower speed and generate less noise for it, so it is the most recommended) and where to place it. Place it over the top case of the Raspberry Pi to see how it would look and where you plan to install it.
The most recommended position is this, especially if you already installed a passive heatsink to the device’s processor (which combined with the fan gives the best result), but you must make sure that it is low enough for the fan to enter without crashing (the fan depth can vary between 6-20mm for this mod, it will depend on which one you bought).
Now you must install the circular saw bit in your drill with the appropriate measurement for the fan (30 or 40 mm, remember) and drill the upper part of the Raspberry Pi case in the position where you are going to install the fan. It is advisable to put a piece of hard cardboard or similar underneath so that when you do the perforation you do not damage what is underneath (sticking it with the double-sided tape).
Once the hole is made, it is recommended that you file the edges to make sure that there are no burrs and that they are left with a perfect finish. This can be done with a fine file by hand, but also if you have a drill bit with a file or a Dremel with the right accessory for it. We recommend that you run the drill / Dremel at low rpm, as the friction will generate heat that could melt the plastic in the case.
Once the main hole is made, you need to drill four more holes for the fan screws. Simply place the fan on top of the hole making it coincide, mark where the holes should go and drill them with the drill. At this point you can also take a dust filter and make holes in it if you want (in some kits they are already cut to size for the Raspberry Pi fan). Once done, simply anchor the fan with the screws.
Once this is done, it only remains to connect the fan to the Raspberry itself. In the following diagram we show you where you should connect its two pins.
Once connected, simply close the case and you can enjoy your Raspberry Pi with active cooling.
With this simple mod, consistent as you have seen in making a custom hole and installing a fan in the Raspberry Pi case, you can significantly reduce its temperature. In combination with a low profile passive copper heatsink, the processor should not exceed 50ºC even at maximum load, which will allow you to avoid thermal throttling while getting the most out of your device and, in fact, you will have room to even overclock if you want.