SeeedStudio recently launched the DeskPi Super6C CM4 Cluster board which can accommodate up to 6 Raspberry Pi CM4 modules. This cluster board comes with a mini-ITX form factor providing access to 2x GbE LAN ports and M.2 sockets for each CM4 module.

As seen below, the Super6C offers one M.2 socket and one MicroSD card slot to each CM4 module. The product can boot from eMMC, SD card or via netboot. Additionally every CM4 module has access to one microUSB port and one 5V fan connector. 

DeskPi Super6C CM4 Cluster board back
(click image to enlarge)

According to the product page, only the first CM4 module has access to two USB 2.0 ports, two HDMI ports, and two USB Host via header pins. 

It was specified that the modules interface with each other using the onboard 1 Gbps switch and each module gets its own IP address. Also the board can work with any amount of modules.

DeskPi Super6C block diagram (left) and schematics (right)
(click images to enlarge)

The Super6C board can be used for applications as home servers, cloud apps hosting or just as a platform to learn cluster applications such as Docker Swarm, Kubernetes, etc.

DeskPi Super6C front edge (left) and side views (right)
(click images to enlarge)

There is a GitHub available providing information about schematics, pinouts and instructions to set up the cluster board. See this link to obtain the manual in PDF format. 

Specifications listed for the DeskPi Super6C include:

• SoM Support:
  • Up to 6 Raspberry Pi CM4 (with or without eMMC version)
• Display:
  • 1x HDMI 2.0
  • 1x HDMI 1.4a (Connect to Primary CM4)
• Connectivity:
  • 2x GbE RJ45 LAN ports 
• Expansion:
  • 6x M.2 2280 slot
  • 6x TF card slots
• USB:
  • 6x Micro USB 2.0
  • 2x USB-A 2.0
  • 2x Host 2.54 Pins (Connect to Primary CM4)
• Other Features:
  • 6x 5V Fan header 
  • 3x 12V Fan header
  • 6x LED indicators
• Power:
  • 19V to 24V / 100W DC
  • 12V ATX power supply
• Dimensions:
  • 170mm x 170mm x 21mm (Mini-ITX)

 Further information

The Raspberry Pi CM4 Cluster Mini-ITX board is available for $199 on Seeedstudio’s online store. The board is also available on Deskpi.com for the same price and on Amazon.com for around ~$249. The product package also includes one 1x 100W power supply.