Radxa unveiled a “Rock 3 Model B” SBC with the same RK3568 as the Rock 3A but with the addition of WiFi/BT, a second GbE port, native SATA, and M.2 B-key and SIM slots for 4G/5G instead of E-key.

A few days after announcing a developer-only launch of its Raspberry Pi style, Rockchip RK3568 based Rock 3 Model A SBC, Radxa has posted images and preliminary specs for an upcoming Rock 3 Model B. This larger board offers native SATA and dual GbE ports, enabling improved support for NAS and networking applications.

Rock 3 Model B prototype, front and back
(click images to enlarge)

The Rock 3 Model B is roughly based on the Pico-ITX form factor, but with some changes that led Radxa to dub it the Pi-Co ITX. These include the alignment of all major ports on one side and a 40-pin Raspberry Pi GPIO connector.

Rock 3A

The board will be larger than Pico-ITX, although a subsequent post suggested it is only increasing from 100 x 72mm to 100 x 75mm. In any case, Radxa says that this should be large enough to fit an M.2 2242 LTE/5G module or 2230 WiFi module, as well as mount an M.2 2280 SSD module without requiring the raised adapter board used by the Rock 3A and Rock Pi 4.

The incomplete specs for the Rock 3 Model B are highly preliminary. The current prototype shares many features of the $35-and-up Rock 3A, starting with the up to 2.0GHz, quad -A55 Rockchip RK3568, which has a Mali-G52 EE GPU and a 0.8-TOPS NPU.

The Rock 3B similarly supports up to 8GB LPDDR4 with 3200MT/s throughput and offers an empty eMMC slot. Like the Rock 3A there are 2x USB 3.0, 2x USB 2.0, and a USB Type-C port with QC/PD power support. Instead of using SERDES multiplexing to offer optional SATA support via the USB 3.0 ports, the Rock 3B gives you a native SATA interface.

Rock 3 Model B prototype (left) and preliminary block diagram
(click images to enlarge)

Instead of using the SDIO interface for a microSD slot, the SBC uses the interface to provide onboard WiFi. In place of the M.2 E-key slot for WiFi, there will probably be an M.2 B-key slot that will support 4G/5G with the help of a SIM card slot, as well as SSDs.

The B-key interface is limited to PCIe 3.0 x1. Radxa may decide to fit this with an adapter that will enable adding a 2230-sized WiFi 6 module. Otherwise, Radxa may take the simpler route of switching this back to an M.2 E-key, which is shown on the preliminary block diagram above.

Like the Rock 3A, there is also an M.2 M-key slot that supports NVMe with PCIe 3.0 x2. The Rock 3B also similarly provides an HDMI 2.0 port, audio jack, and RTC with battery connector. We saw no mention of the PoE support available with the Rock 3A’s single GbE port.

Presumably, the Rock 3 Model B will offer the same Debian 10 image provided for the Rock 3A, which starts shipping in volume in late August. All the Radxa boards are available with schematics and other open source resources and are community supported.

 
Further information

No pricing or availability information was provided for the very preliminary Rock 3 Model B. More information may be found on Radxa’s forum page.