Raspberry Pi 400 Features and Upgrades

The Raspberry Pi 400 marked a significant departure from previous Raspberry Pi models by integrating a complete computer directly inside a compact keyboard chassis. While built on the foundation of the Raspberry Pi 4 architecture, this model introduced several distinct hardware redesigns, performance enhancements, and layout changes tailored for an all-in-one desktop experience. This article breaks down the primary features and upgrades introduced in the Raspberry Pi 400 compared to its traditional single-board predecessors.

Integrated Form Factor and Design

The most obvious introduction was the form factor itself. Inspired by classic 1980s home computers like the Commodore 64, the Raspberry Pi 400 houses its completely redesigned, elongated printed circuit board (PCB) inside a 78-key compact keyboard. This eliminates the need for an external keyboard and a separate protective case, making it a highly portable, plug-and-play desktop solution.

Boosted Processor Performance

While the Raspberry Pi 400 utilizes the same Broadcom BCM2711 quad-core ARM Cortex-A72 64-bit silicon found in the Raspberry Pi 4, it features an upgraded “C0” processor stepping. This refinement allows the Raspberry Pi 400 to come factory-clocked at 1.8 GHz out of the box, offering a 20% performance increase over the standard 1.5 GHz clock speed of the early Raspberry Pi 4 Model B.

Advanced Passive Cooling

To manage the thermal output of the faster clock speed without a loud fan, the Raspberry Pi 400 introduced a massive, internal aluminum heatspreader. This built-in passive cooling system spans nearly the entire length of the keyboard housing. It shields the processor from thermal throttling under heavy workloads, allowing it to run significantly cooler and completely silent compared to a bare Raspberry Pi 4.

Dedicated Power Button and Indicator

Unlike older models that require users to unplug the USB-C cable or purchase an inline switch to cut power, the Raspberry Pi 400 integrated dedicated power management directly onto the keyboard. By holding down the F10 function key, users can safely power down or turn on the system. The keyboard also features an integrated LED indicator that serves as a combined power and disk activity light.

Port Adjustments and Omissions

To accommodate the desktop layout, all connectivity ports were rearranged along the rear edge of the keyboard. This came with several notable adjustments to the standard I/O configuration:

• Spring-Loaded MicroSD Slot: The storage slot was upgraded to a click-in, click-out spring mechanism, making card swaps easier and more secure than the friction-fit slots on previous boards.
• Rear-Facing GPIO: The standard 40-pin GPIO header is accessible horizontally from the back of the case, though its recessed nature means certain HATs require a extension ribbon cable.
• USB Configuration: The port selection includes two USB 3.0 ports and one USB 2.0 port, dropping one of the USB 2.0 ports found on the Pi 4 to accommodate the internal keyboard connection.
• Kensington Lock Slot: A Kensington Security Slot was added to the side of the chassis, allowing the computer to be physically tethered to a desk in educational or public environments.

Removed Legacy Interfaces

In streamlining the device for a standard desktop workflow via HDMI and Bluetooth, several legacy and maker-centric ports were completely omitted from the Raspberry Pi 400 hardware:

• No 3.5mm Audio/Composite Jack: Audio output is restricted to digital options via the dual micro-HDMI ports or wirelessly through Bluetooth 5.0.
• No Camera (CSI) or Display (DSI) Interfaces: The internal ribbon connectors used to plug in official Raspberry Pi camera modules and touchscreen displays were removed.
• No Power over Ethernet (PoE): Because the board shape does not support standard PoE HATs, it cannot be powered via an Ethernet cable.