On the Radxa website there is a lot of information about the Rock 4 SE, but it is confusing. This makes it more difficult to get started. The downloads for the SE refer to Armbian images for Pi 4A/B and Pi 4C, which confused us.
We wrote the Radxa image for Debian Bullseye with XFCE desktop as instructed using BalenaEtcher to a microSD card. The computer started up without any problems, but some work was needed to customize everything, because the operating system started up with an English interface, US time zone, and the default user rock with the password rock.
Problems with USB port and update distribution
The top USB 3.0 port does not work because it is configured as a client device instead of a host port for USBOTG. Updating the distribution with sudo apt-get update && apt-get upgrade failed because we had to import a key from a Radxa server first. The HDMI output delivered 4K resolution, but no sound.
Armbian images and DietPi
The Armbian images are more user-friendly and prompt for the desired localization of the keyboard and interface on first boot. They also force you to set up a new user and root password. With Armbian, HDMI sound worked, but at most full HD resolution was possible. DietPi worked in our tests, but also only showed full HD resolution at most.
Boot from different storage media
In addition to a microSD card, the Rock 4 SE can also boot from eMMC flash or an M.2 SSD. We wrote an image to the eMMC module and the system booted, but we got errors when accessing the flash memory. The cause of this is not clear.
To boot from an M.2 SSD, you must overwrite the firmware in the SPI flash memory chip with a different version and modify the bootloader on the storage medium. However, we have not tested this.
Compatibility list for M.2 SSDs
Radxa maintains a compatibility list for M.2 SSDs that include the Intel SSD 660p and the Kingston A2000. Both also worked during our testing. However, a Samsung SSD 960 Pro was not recognized and was also missing from the Radxa list.
Installation of OMV
After flashing the aforementioned Armbian 22.11.1 Bullseye Current to a microSD card, we were able to install OMV without any problems using armbian-config and choose the NVMe SSD as the storage medium. With this, the Rock 4 SE achieved the usual speeds for gigabit Ethernet of about 110 MB/s for both writing and reading.
However, the problem may be that when using longer M.2 SSDs in 2280 format, they protrude over the edge of the printed circuit board and there is no possibility to secure them. This makes for a shaky construction.