Quick review: Geekworm Model B Armor for Raspberry Pi 4

I received the Model B Armor case by Geekworm in the mail today, which I ordered the case a little over a week ago from China because of the well known temperature issue with the Raspberry Pi 4. To determine the core temperature of the Pi, I use the vcgencmd utility. It has been returning me results like this:

pi@raspberrypi:~ $ sudo vcgencmd measure_temp

I've had a 4GB model running for a few weeks now, and is consistently runs at over 60 degrees Celsius without any significant load. Ambient temperature is around 20 degrees. Initially I had it running with the official Raspberry Pi 4 case. Since that case is completely closed off, I tried a case with more openings, in the hope that some of the heat would be driven off. This had no effect.

Hence the choice for the aluminum case specifically designed to deal with this. I chose the edition with fans because I feared only passive cooling might not be enough. 

Installation and temperature reduction
Installation is easy. The package comes with some thermal tape to attach to the Pi. The case fits very nicely. It feels like I've ordered some quality. After screwing everything together, plugging in the fans and starting the Pi back up, I let the Pi run for a few minutes. Then I check the new temperature values. The result it fairly significant:

pi@raspberrypi:~ $ sudo vcgencmd measure_temp

The core temperature dropped nearly 25 degrees. It stays at that value too.

Fan noise
Geekworm advertises that the fans only produce 18 decibels. This fact, as well as a review on YouTube pretty much confirming the near silence of the fans, convinced me to go for this option. I have to say I am a bit disappointed here. I don't have a method to reliably determine the actual sound production, but what I can say is that I do clearly hear the fans. In fact, I'd call them fairly loud. I have an Intel Nuc (which has fans) running near the Pi, and while the Nuc is hardly noticeable, the fans from the Geekworm casing produce the loudest sound in the room. 

Without fans
So what does the temperature do with the fans unplugged? As to be expected, there is a difference. The temperature creeps up slowly but steadily to reach 50.0 or 51.0 degrees after about an hour. Thus, about 50% of the temperature reduction seems to be in the fans, under low load conditions.

Temperature under load?
All these values are with the Pi running pretty much just Raspbian and nothing else. I may add some results from tests under heavier load at a later date.

Update november 2019

A colleague of mine brought it to my attention that a firmware update for the Raspberry Pi 4, released in October, was supposed to reduce its heat production. After installing it, I did indeed note a difference in the registered temperature. I might note that since the previous test I did was in August, and it now November, ambiant temperature will be lower as well. Additionally, I currently have the Pi attached to a wall with a mount which allows some room between the the back side and the wall. This might also help with heat dissipation. Regardless, I registered temperatures as much as 10 (!) degrees lower than the values mentioned above with the fans turned off. I'm looking at 41.0 or 42.0 degrees now. 

On top of that, since I always had the fans turned off, I've ordered the fanless version of this case. Result is a further reduction of temperatures to 36.0 to 37.0 degrees! This is lower than the values given out by a Raspberry Pi 3B+ sitting next to the Pi 4.

pi@raspberrypi:~ $ sudo vcgencmd measure_temp

This changes everything. Even if ambian temperatures would rise, resulting in temperatures above 40 degrees, it is still entirely acceptable.