The Raspberry Pi 4 runs hot, specially when overclocked. As I use it as my programming machine for my personal projects, I wanted to get the most out of its CPU.

The first case I ordered for my Pi came with a fan which worked on 3.3V and 5V (too noisy). I setup a circuit which would allow me to turn it on/off via a GPIO pin controlled by this python based service, which turns the fan on/off based on certain threshold temperatures. This did work but the idling Pi would always go beyond the threshold temperature turning the fan on when. With the threshold at 65°C. I was getting 1:10 on:off ratio, which meant fan noise every 10 minutes of idle time.

I spent some time trying to figure out the best cooling setup for the Pi with a target of staying cool with a sustained load. To test the cooling setup, I wrote this script. The key benchmarking command that the script run is:

sysbench cpu --threads=4 --events=200000 --time=0 --cpu-max-prime=100000 run

I did not get satisfactory results with my plastic case + small heat sink + fan setup. Eventually, I found a way to purchase a fantastic passively cooled case: Argon Neo. It looks great and works as a heat sink itself. With the Neo, I now have a silent setup which would sustain long running CPU bound tasks with an even higher overclock of 2100 MHz without throttling.

A few of the results from the numerous benchmarks I did with the script:

A few observations I made with the Neo:

• Neo performs much better without the cover on because of insufficient thermal connectivity between the cover and the case.
• Adding a fan made not much of a difference. Specially with the cover when there is no ventilation.
• The case works better when the room fan is on which is likely when I am working on the Pi. I observe 3-4°C lower temperatures.
• The included thermal pads performed much better than the thermal paste I had with me.
• Although the case is Aluminium, I didn’t observe much impact on the wireless signal. Likely because of the plastic base.

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