Raspberry Pi has long been the gold standard for inexpensive single-board computing, powering everything from robots to smart home devices to digital kiosks. The Raspberry Pi 4 takes Pi to another level, with performance that’s good enough to use in a pinch as a desktop PC, plus the ability to output 4K video at 60 Hz or power dual monitors.
For the same $35 starting price as prior models, you get speeds that are two to four times faster, support for USB 3 and true Gigabit Ethernet. Perhaps more importantly, there is a $45 Raspberry Pi 4 with 2GB of RAM and a $55 unit with 4GB, four times more than any previous Pi has had. Makers and hobbyists should add the Raspberry Pi 4 to their arsenals, and tech enthusiasts who’ve never used a Pi before now have even more reasons to buy one.
While there were some apps that needed updating at launch time, almost everything that ran on the Pi 3 B works on the Raspberry Pi 4 B. If you have old microSD cards from a prior Pi build, they may not work, because the Pi 4 B requires Raspbian Buster, the lastest version of the platform’s official OS. Support from other operating systems such as Ubuntu has also improved.
However, game emulation is still flagging a bit (see below). And because of the subtle differences in the design (dual microHDMI ports, USB-C power), any case that was designed to hold the Pi 3 B will not fit.
Game Emulation or Lack Thereof
Nearly five months after launch, Retropie, the very popular gaming emulator software, does not officially support the Raspberry Pi 4 out of the box. There’s a workaround that allows you to install and use Retropie on a Raspberry Pi 4, but it’s not officially supported and it takes some time to do.
Lakka, an alternative to Retropie, now does officially support the Pi 4. However, this emulation platform isn’t as full-featured or attractive as Retropie.
|Spec||Raspberry Pi 4 B||Raspberry Pi 3 B+|
|CPU||1.5-GHz, Quad-Core Broadcom BCM2711B0 (Cortex A-72)||1.4-GHz, Quad Core Broadcom BCM2837B0 (Cortex A-53)|
|RAM||1 – 4GB DDR4||1GB DDR2|
|GPU||500 MHz VideoCore VI||400 MHz VideoCore IV|
|Video Out||dual micro HDMI ports||single HDMI port|
|Max resolution||4K 60 Hz + 1080p or 2x 4K 30 Hz||2560 x 1600|
|USB Ports||2x USB 3.0 / 2x USB 2.0||4x USB 2.0|
|Wired Networking||Gigabit Ethernet||330 Mbps Ethernet|
|Wireless||802.11ac (2.4 / 5 GHz), Bluetooth 5.0||802.11ac (2.4 / 5 GHz), Bluetooth 4.1|
|Charging Port||USB Type-C||micro USB|
|Power Requirement||3A, 5V||2.5A, 5V|
|Size||3.5 x 2.3 x 0.76 inches (88 x 58 x 19.5mm)||3.2 x 2.2 x 0.76 inches (82 x 56 x 19.5mm)|
|Weight||0.1 pounds (46 grams)||0.11 pounds (50 grams)|
The most important new features are the faster processor and GPU, more and faster RAM, the addition of USB 3 ports, dual micro HDMI ports instead of a single HDMI connection and support for 4K output. The higher bus speed that enables USB 3 support also allows the on-board Ethernet port to support true Gigabit connections (125 MBps) where the last-gen models had a theoretical maximum of just 41 MBps. The microSD card slot is also twice as fast, offering a theoretical maximum of 50 MBps versus 25 MBps on the 3B+.
Because the new SoC needs more power, the Raspberry Pi 4 B charges over USB Type-C instead of micro USB. It also requires a power adapter that can deliver at least 3 amps of power and 5 volts, though you may be able to get away with 2.5 amps if you don’t attach many peripherals to the USB ports. Putting aside the power needs, USB Type-C connectors are reversible, which makes them much easier for kids (and adults) to plug in.
After we first published this review, we found out that some USB Type-C cables don’t work with the Raspberry Pi 4. Those cables that are “electronically marked” will see the Pi 4 as a USB audio device and not provide power. Only USB-C to USB-C cables can be electronically marked and you only find this on cables that operate at 5 Gbps or higher. In our tests, we found 11 low-cost USB-C cables that work with the Raspberry Pi 4 and only found a few cables, all USB 3.1, that did not. If you buy Raspberry Pi’s official Pi 4 charger, which comes with a cable, you also won’t have a problem. The Pi foundation says it will fix the problem on future builds, but it can’t be solved via a firmware update.
At 3.5 x 2.3 x 0.76 inches (88 x 58 x 19.5 mm) and 0.1 pounds (46 grams), the Pi 4 is thin enough to fit in your pocket and light enough to carry anywhere. The board is durable enough to probably survive rolling around in your bag, but we recommend sticking it in something protective, mostly to protect the pins. However, during testing, I always used the board bare on my desk and I carried it back and forth between work and home many times by simply putting it in a cardboard box with no padding or static bag.
Unfortunately, if you want a case, you can’t use one that’s been designed for any previous Raspberry Pi. The Raspberry Pi 3 B / 3 B+ have almost the same dimensions, but the port layout has changed just enough to make the Pi 4 B incompatible. Where prior Pis had a single, full-size HDMI port, the dual micro HDMI connectors on the Pi 4 jut out more and so don’t line up with the holes on anything that was designed for the Pi 3 B. We really like the Pimoroni Pibow, a $10 / £8.50 case that looks really good and doesn’t cover over the GPIO pins.
The Raspberry Pi 4 covers more than just the basics when it comes to ports. The right side has four USB Type-A connections, two of which are USB 3.0. There’s also a full-size, Gigabit Ethernet port for wired connections there. The bottom edge has a 3.5mm audio jack, two micro HDMI ports and the USB Type-C charging port. On the left side, you’ll find the microSD card reader.
And on the top surface of the board, you’ll see ribbon connectors for the Camera Serial Interface (CSI) and Display Serial Interface (DSI), which provide dedicated connections to Raspberry Pi’s own camera and screen (or compatible accessories). Of course, you can connect a camera to a USB port as well and there are a couple of more common ways, including the micro HDMI ports, to output to a screen.