Raspberry Pi 4 Model B review: Back, and better than ever
Thermal issues aside, this is one seriously tasty Pi
It’s easy to forget just how impressive a feat of engineering the Raspberry Pi actually is. It’s become such a fixture of the tech world that it’s sometimes taken for granted, but take a step back and it’s nothing short of miraculous. Here is a device that’s roughly the size of a pack of cards, and yet it’s powerful enough to act as a full-on desktop workstation, as well as a hobbyist board, headless controller and numerous other tasks - all for less than the price of a return train journey from London to Raspberry Pi’s Cambridge headquarters.
Not content to rest on their laurels, the Raspberry Pi team has been hard at work cramming even more performance and functionality into the Pi’s tiny frame and the result - just over two years after creator Eben Upton told us of the “long road” it would take to get here - is the Raspberry Pi 4.
It may not look like much, but the Pi family is proof that humble looks can be deceiving, and there’s a lot of new tech under the hood, including a new manufacturing process allowing Upton and co to squeeze increased speed out of the Pi’s Broadcom SOC. There’s also a selection of new, faster ports and, for the first time, the ability to output to multiple monitors.
With so much goodness baked in, let’s slice it open and find out what makes this Pi quite so tasty
Raspberry Pi 4 Model B review: Design
Let's get the obvious out of the way first. The latest addition to the Pi family looks near-identical to its siblings. It follows the same footprint as the Pi 3, using a board of the same size and weight. Beyond a first glance, you'll see that the port layout has had a bit of an overhaul.
Most notably, the USB ports and Ethernet port have been switched around, so that the USBs now sit on the left of the board. The single large HDMI port has been stripped out and replaced by two much smaller micro HDMI ports, and power is now supplied along a USB-C port, rather than a micro-USB.
This means that you almost certainly won't be able to use the Pi 4 with any cases or enclosures designed for older models and you can't swap out the old Pi powering an existing project, which is understandable (if a bit of a shame). Aside from these changes, it's still the same old Pi, with its circuitry exposed and the GPIO pins along the right-hand side.
Raspberry Pi 4 Model B review: Ports and features
New ports bring new capabilities, most notably the ability to output to two 4K monitors at 60fps via the two new micro HDMI ports. Although the Pi 4 has a USB-C port, this is sadly exclusively used for powering the device, so you can forget about using it as a one-cable connector.
Elsewhere, two of the four USB ports now use the faster USB 3.0 standard as opposed to the older, slower USB 2.0 specification. Gigabit Ethernet is still present and correct (as is the ability to use PoE via a HAT), and the composite A/V, DSI display and camera ports have all made the jump as well.
Dual-band 11ac WiFi and Bluetooth 5.0 are included on the board, and both come with modular compliance certification out of the box to speed up prototyping and manufacturing processes.
Raspberry Pi 4 Model B review: Specs and performance
The headline news here, however, is the performance. The Pi 4 is the fastest Pi ever, thanks in large part to the fact that the company has moved from a 40nm manufacturing process to a 28nm process, which has resulted in greater efficiency and faster speeds. It's packing a quad-core Broadcom BCM2837 SOC clocked at 1.5GHz and, for the first time ever, there are multiple tiers of RAM available.
The Raspberry Pi 4 comes with either 1GB, 2GB or 4GB of LPDDR4 RAM (the latter of which was the one we tested), which offers a particular boost when it comes to multi-tasking. The 1GB tier retains the Pi's traditional $35 price point, while the 2GB and 4GB options are available for $45 and $55 respectively - which is still great value, considering what's on offer.
So it's definitely faster - but how much faster is a trickier question to answer. We ran it through a number of benchmark tests, including the HardInfo and Whetstone benchmarks, with mixed results. In the Whetstone and FPU Raytracing tests, it managed to exceed the Pi 3 B+ by 55%, but it was 127% better at the CryptoHash benchmark and 95% faster in the Dhrystone tests. In general, it was considerably faster than the previous generation, although how much faster it will feel in practice will depend on what kind of workloads you're using it for.
However, if you're thinking that the Pi is now fast enough to act as an entry-level PC, you should temper your enthusiasm slightly. While it's a good deal faster than the previous Pi, it's still miles off the performance of even the most cheap-and-cheerful Y-series Intel Core processor. In practice, we found performance to be somewhat patchy. Running the device on one monitor didn't present much of an issue, but the Pi slowed significantly when we tried to use it with two displays. With four single-tab Chromium windows open, the Pi was often struggling to keep up - typing would take a second or so to appear, and we had to wait a few seconds before it would register our clicks.
It's also in dire need of inbuilt cooling. The more powerful components evidently generate more heat than previously, because the Pi 4 was hitting the 85 degree threshold on a regular basis, after which performance is throttled to prevent overheating. A little thermometer icon appears in the corner of the screen to indicate when this is happening, and it was pretty much a constant fixture while we were using the Pi.
Removing the Pi's case to allow more airflow helped significantly with this, and speed improved noticeably as a result. If you're planning on using the Pi 4 in any projects, we'd highly recommend purchasing a heatsink or a fan-assisted case to ensure optimum performance. With better cooling, the Pi was stable enough (for the most part) to use as a day-to-day work machine with few incidences of frustrating lag.
Network speeds were good too; while Ethernet speeds were capped at 300Mbits/sec with the previous generation, the new Pi is capable of the full 1,000Mbits/sec offered by the Gigabit standard. This makes it ideally suited to network transfer tasks like acting as a security camera or data gathering device.
Raspberry Pi 4 Model B review: Verdict
While we do have some issues with the Raspberry Pi 4's thermal management and cooling, these can be effectively countered by adding a heatsink. On top of that, we keep coming back to the fact that this is a device which costs less than £50 and is roughly the size of a packet of cigarettes - and yet, we've been comfortably doing all our work on it (bar photo editing) with few complaints.
That really is staggeringly impressive when you think about it. The Raspberry Pi remains a marvel of engineering, and the fact that we're comparing it to traditional desktops at all bespeaks a seriously capable machine.
The Raspberry Pi family is Britain's greatest innovation since the ZX Spectrum, and the Raspberry Pi 4 is its crowning glory. With more versatility, improved performance and faster data transfer, the Pi 4 is nothing short of delicious.
Raspberry Pi 4 Model B specifications
|Processor||Quad-core 1.5GHz Broadcom BCM2837|
|Dimensions||56 x 85 x 16mm|
|Ports||2x USB 2.0, 2x USB 3.0, 2x micro HDMI, 1x DSI, 1x CSI, 1x GbE, 40x GPIO|