All of them offer a more powerful alternative to the $35 Raspberry Pi, but until now none has come close to matching its price.
The RockPi 4 with 1GB of RAM will cost $39, undercutting the NanoPi NEO4 by $10, and bringing it within range of the Raspberry Pi. Many other boards with the six-core RK3399 cost over $100.
Radxa has closely followed the design of the Raspberry Pi and uses the same 40-pin GPIO header, so that buyers can take advantage of the large hardware ecosystem built around the Raspberry Pi's design.
The Rock Pi 4 measures 85mm x 54mm and is available in two variants, dubbed Model A and Model B. The difference between the two is that the Model B has power over Ethernet (PoE) support with the help of Raspberry Pi's PoE HAT, as well as 802.11ac Wi-Fi and Bluetooth 5.0.
Both models are available with 1GB, 2GB or 4GB of RAM and feature a Gigabit Ethernet port capable of 940Mbit/s speeds, according to the specs sheet.