Cases for the Raspberry Pi, including the best Raspberry Pi cases, come in many designs. Plastic laser cut layers and interlocking shells are common choices, but Argon Forty have chosen aluminum enclosures that surround the Raspberry Pi and provide extra functionality for your Pi.
The latest case in the Argon ONE series is the $45 Argon ONE M.2 and it looks identical to their Argon ONE case but keen eyes will notice that it stands slightly taller. The case now features a plastic riser and inside there we find an M.2 SATA to USB carrier board, which provides the SSD interface to enable our Raspberry Pi to boot from SSD.
The ability to boot a Raspberry Pi 4 from a USB SSD is relatively new; it was tested in May 2020 and finally released for general use in September (see how to boot your Raspberry Pi 4 from USB). The process to install Raspberry Pi OS, or other compatible OS to SSD is relatively straightforward and the performance gains it provides are well worth the effort. The Argon ONE M.2 is an intriguing case that offers a fresh take on using a Raspberry Pi. It can turn our Raspberry Pi into a desktop, a media center or home server via the faster SSD interface.
The all aluminum construction and re-routing of ports lends the Argon ONE M.2 to use on your desk. All we are missing is a VESA mount option to hide the unit behind our screen.
Design of the Argon ONE M.2
The Argon ONE M.2, like the Argon ONE that came before it has an angular look to it. The aggressive lines of the aluminum case top provide a sleek aesthetic for what is a comparatively large case, measuring 4.1 x 3.6 x 1.5 inches (105 x 93 x 39mm).
Around the front and sides of the case we see no slots or ports, rather the Argon ONE M.2 follows the design aesthetic of the previous model and routes all of the ports to the rear.. All of the USB ports and Ethernet jack on our Raspberry Pi 4 8GB are present, along with two full size HDMI ports, a USB C port and headphone jack. On a plastic riser, we see an additional USB 3.0 port, and this is used to connect the internal M.2 SATA drive to the USB of the Pi.
Building the Argon ONE M.2
Assembling the Argon ONE M.2 involves a few steps. First, I need to connect an M.2 SATA drive to the adapter. M.2 SATA 2242 to 2280 drives are supported and are held in place with a screw. Make sure you use an M.2 drive that’s SATA as most these days are NVMe and won’t be compatible.
Connecting the Raspberry Pi 4 to a custom board used to breakout the micro HDMI ports to full size HDMI and to extend the headphone jack to the case edge, is simply a matter of pressing them into one another. Place the thermal pad on to the System on Chip (SoC) and then insert your micro SD card before connecting the Raspberry Pi to the GPIO extension header inside the case. This will also connect the CPU and thermal pad to the case passively cooling the Pi.
A few screws and the bottom case are secured to the main unit. To connect the SSD to the Raspberry Pi we need to use the included adapter which connects the USB 3.0 port of the SSD adapter to one of the USB 3.0 ports of the Pi. Unfortunately, the adapter is slightly oversized and can make inserting other USB devices tricky. Now all we need to do is connect our accessories and power up the Raspberry Pi.
Using the Argon ONE M.2
The Argon ONE M.2 is designed for use with SATA SSD, so much so that the micro SD card slot is not accessible. For our first boot we flashed Twister OS, Raspberry Pi OS with extra features, to a micro SD card and then booted. Following our guide to installing and booting Raspberry Pi OS from USB we transferred the install to SSD, powered off the Pi and then removed the micro SD card.
First boot with the SSD will take a little longer, as the Raspberry Pi checks and configures itself. Subsequent boots will be much quicker. Our average SSD boot time was 26.82 seconds, the same amount of time as a good quality micro SD card. Where the SSD really adds benefit is in general operating activities. Using applications and file management see the biggest boost in speed, an almost “desktop” experience.
To control and configure the onboard fan we need to download and install a script from Argon Forty. Once it is , you can use the Argon application to control the fan speed and behaviour at set temperatures.
The Raspberry Pi is nothing without its GPIO (see the Raspberry Pi GPIO pinout) and the Argon ONE M.2 has a hatch on the top of the case that permits access to a GPIO breakout. The GPIO is labelled and color coded based on the purpose of each pin.
To use any HATs, including the best Raspberry Pi HATs, you have two options: a breakout board such as the Black HAT Hacker from Pimoroni or a GPIO extension header to raise the board above the case. HATs and add ons will need to be placed so that they hang over the back of the case, not over it. The orientation of the GPIO breakout is awkward but not a deal breaker if you are willing to use a breakout. If you are looking to build projects, then Argon ONE M.2 is a viable option, but you do need to take the GPIO issue into account.
Argon ONE M.2 Operating Temperatures
With my Raspberry Pi 4 running at stock speed the Argon ONE M.2 idle temperature was 44 Celsius, just 4 degrees Celsius higher than a bare Raspberry Pi 4 and mainly due to the case acting as a large heatsink with a skin temp of 30.2 degrees. WHen we ran the Stressberry test, which taxes the CPU, the temperature rose to 54 degrees , 11 lower than our stock Raspberry Pi 4, which ran at 65 degrees.
If the temperature had risen to 55 degrees, the Argon ONE M.2 fan would’ve kicked in at 10% power and gently cooled the Pi below the trigger point. The case’s skin temperature was 30.2 Celsius, warm but not uncomfortable.
To push the Argon ONE M.2, we overclocked the CPU to 2.1 GHz and saw the case skin temp rise to 34 degrees, and the idle temperature oddly drop to 40 degrees. Running Stressberry at 2.1 GHz, we saw the temperature rise to 58 degrees , with the fan triggering at 55 degrees responsible for keeping the temperature below 60. The post Stressberry temperature stabilized at 45 degrees, slightly warmer than the idle temperature. Considering that the Raspberry Pi throttles at 80 degrees, peak performance was never in danger.
Use Cases for the Argon ONE M.2
With an SSD in the Argon ONE M.2, the Raspberry Pi 4 is a desktop computer. Sure it won’t be your main machine, but you can get a lot done with this setup. The ideal use for the Argon ONE M.2 is as a second computer; the design of the case lends itself to this task. Media consumption device is another option. A large M.2 SATA SSD could be used to store your media and as the boot device. OSMC, a popular media OS, needs less than 1GB of space.
The Argon ONE M.2 is a great all round case, It keeps our Raspberry Pi 4 cool even under heavy loads. It looks great, and being the first case with an M.2 SATA drive option means that we have cheap, fast and reliable storage for our Raspberry PI without using external USB drives. It is by no means the only solution on the market, with the DeskPi Pro and its M.2 NVMe drive interface on the horizon we may see competition in the not too distant future.