We previously noted it was possible to build a Raspberry Pi CM4 NAS using Wiretrustee carrier board with a built-in Marvell 88SE9215 PCIe to SATA controller and four SATA connectors.
But Mebs just created his own Raspberry Pi Compute Module 4 four-bay NAS with his own carrier board equipped with a PCIe socket used to insert a PCIe SATA card, as well as a neat 3D printed enclosure that took 6 days to print.
This carrier board design is actually derived from the official Raspberry Pi CM4 IO board with only the interfaces needed for the NAS to make it smaller and fit within the width of a standard 3.5″ hard drive. It was also made as simple as possible because it was Mebs’ first PCB design.
This leaves the board with Gigabit Ethernet, one HDMI port, a USB 2.0 port, the PCIe 2.0 socket, as well as some headers for power (board and SATA), a small I2C OLED display, temperature sensor, GPIOs, and fan control.
Details about the carrier board and 3D printed case can be found on Github, but I could not find detailed assembly instructions for the complete NAS. But since photos were shared we can see the Raspberry Pi Compute Module 4 plugged into the RPI CM4 NAS carrier board, a PCIe card with four SATA ports, a fan, and how the drives are placed on the sides of the enclosure.
The unit shown above with three hard drives installed is said to draw around 24W under full load and under 6W at idle, while performance is around 110MB/s sequential read and write. However, he noticed occasional dips down to 15MB/s for a second or two during sustained operation and noted software optimization may be possible.
You’ll find a few more details and photos in the Reddit thread where Mebs announced the project’s completion. There does not appear to be any plan to sell the board or the full kit NAS, so that’s a project you’d have to complete yourself from the soldering of components in the board, 3D printing of the enclosure, and software installation.