A new board in the Rock Pi 4 (opens in new tab) family of Raspberry Pi alternatives has appeared - brought to our attention by CNX Software (opens in new tab). It's the Model C+, which uses downclocked processor cores in its SoC to undercut its own elder sibling, the Model B+, on price.
There are a few other differences, in that the C+ sports two micro HDMI ports instead of the B+’s full-size one, and doesn’t feature the onboard flash storage that’s a feature of the B+, but otherwise they appear similar.
The SoC is the Rockchip RK3399T, which has six cores. Two of them are Cortex-A72, the kind found in the Raspberry Pi 4 (opens in new tab), which run by default at 1.5 GHz instead of the 2 GHz of the OP1 in the B+ model. They can, of course, be overclocked, but only to 2 GHz, whereas the OP1 can manage 2.4 GHz. The remaining four cores are Cortex-A53, seen in Amazon Fire tablets and the Nintendo Switch. These run at 1.4 GHz instead of 1.5 GHz. The GPU is the same Mali T860MP4 on both C+ and B+ boards, and the 4GB of RAM is the same LPDDR4 running at 3200Mb/s.
Storage comes via a Micro SD card slot, though there's also an unpopulated eMMC socket that can take up to 128GB, and an M2 socket can accommodate a 2TB SSD with its transfer rate capped by the PCIe 2.0 x4 interface. There's a gigabit Ethernet port, with an optional HAT to add PoE capability, and both Wi-Fi (dual-band AC) and Bluetooth. Expansion comes via two USB 3 and two USB 2 ports, plus a 40-pin GPIO array. And there's even a power button.
Speaking of which, you’ll need to feed the C+ 5V at 5A via the USB-C port if you want to use an SSD, but the board is content with 5V at 3A if you don’t. The board’s dimensions are just 3.3 x 2.1 inch (85 x 54mm), and it will run Debian, Ubuntu, Android (7, 9, or 11) officially (opens in new tab), with open-source graphics drivers coming via Panfrost.
The HDMI ports are worth a second look, as they support different resolutions. One can manage 4K at 60Hz, while the other is limited to 2K at the same refresh rate. There's also a MIPI connector for extra screens, and ribbon connectors for a camera too, as long as you’re ok with a maximum resolution of 8MP.
The Rock Pi 4 C+ is on sale at AllNetChina (opens in new tab) for $59.99 + shipping at the time of writing, with Ameridroid (opens in new tab) carrying it for $5 more. By contrast, the B+ with 32GB of eMMC is $75 or $87 on the same sites.