What is it?

The CM4 Ether Board is a compact, no-frills carrier board for the Raspberry Pi CM4 and other compatible compute modules. It has a streamlined form factor that fits vertically in a 1U server rack or can be tucked away inside an enclosure.

It provides a compact platform for tinkerers creating a cluster or setting up their home lab. Since the main application for the CM4 Ether Board is to be used as a server or as a node in a cluster, it includes an M.2 connector for NVMe SSDs. An onboard converter supplies reliable 3.3v (up to 3A) power, which is plenty of juice to power most NVMe SSDs.

The board is powered through a USB-C port and sports an additional Micro USB port for connecting downstream devices (think: webcam, card reader, or a 3D printer).

The Micro USB port also supports device mode, which can be used to flash an OS to the CM4. This board does not support modules without eMMC as it does not have a card reader (this might change in future versions).

I manually assemble, solder, and test these boards in my workshop.

The CM4 Ether Board is also compatible with the Radxa CM3, given you make some modifications to the device tree.

Details

• 1Gbps Ethernet Jack
• M.2 Connector for 2230 NVMe SSD (M key)
• 1 USB Micro Port for devices or flashing the CM4
• 1 USB-C Port for Power
• Built-in ESD protection
• Dedicated solder jumpers to disable WiFi and Bluetooth

A simple jumper is used to change the CM4 from Device Mode for flashing the CM4 or Host Mode, to control downstream devices like a 3D printer or USB camera.

What You get

Obviously, this listing does not include the Raspberry Pi CM4 or the SSD in the pictures :)

• CM4 Ether Board
• M.2 Screw
• Jumper

Examples

Here is 4 Raspberry Pi CM4s mounted to a server/studio rack. STL files available for free.