This is the most comprehensive performance review of the newly released Raspberry Pi 4 seen by Teacher Su, conducted by a foreign expert. Teacher Su saw the information translated by Google on the public account “Electronic Engineer Time” and made some formatting and font adjustments. Many thanks to the editors of “Electronic Engineer Time” for taking the time to translate such great content into Chinese (albeit machine translated) and publish it on the public account. An English original is also attached for friends who prefer to read professional materials in English. English link: https://www.tomshardware.com/reviews/raspberry-pi-4-b,6193.html. Today, I take this opportunity to share it with everyone!
Below is the translated article content:
The Raspberry Pi has long been the gold standard for low-cost single-board computing, serving a variety of purposes for robotics, smart home devices, and digital kiosks. The highly anticipated Raspberry Pi 4 takes the Pi to another level, with performance sufficient to be used as a desktop PC, capable of outputting 60 Hz 4K video or powering dual displays.
RASPBERRY PI 4
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Much faster than previous Raspberry Pi versions
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USB 3 ports
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Capable of outputting 4K video at 60 Hz
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Support for dual displays
Cons:
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Key software does not work at launch
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Poor performance with high-resolution video playback
Conclusion:The best Raspberry Pi is faster and more powerful than any predecessor without raising the price.
Score:4.5 / 5
For the same starting price of $35 as previous models, you can get two to four times the speed, support USB 3.0, and true gigabit Ethernet. Perhaps more importantly, there will be a $45 Raspberry Pi 4 with 2GB of memory, and a $55 version with 4GB, which is four times that of the previous Pi. Manufacturers and hobbyists are eager to add the Raspberry Pi 4 to their arsenal, and now tech enthusiasts who have never used a Pi have more reasons to buy it.
Raspberry Pi 4B. (Image source: Tom’s Hardware)
We had the opportunity to get an early look at the Raspberry Pi 4 B, which is the full name of the first Pi 4 model, and were able to test the circuit board with a complete 4GB of RAM. What we see is a fully functional mini-computer. We are particularly excited about the possibilities for inference, especially object and sound detection.
Backward Compatibility
It is worth noting that at launch, some key Raspberry Pi software was not running on the Pi 4. To run the Pi 4, you need to download a brand new version of the Raspbian OS called Raspbian Buster. Not everything is compatible with Buster. During testing, we discovered many Python libraries or other essential packages that were not compatible with the new operating system.
As of this writing, you also cannot install Retropie (a very popular game emulator software) on Buster (believe us, we spent hours trying), nor can you use existing Retropie images. Developers will undoubtedly make adjustments in the coming days and weeks, but if you are reading this at launch and need to build an arcade in the near future, you might want to get an older model. Third-party Raspberry Pi operating systems also need some adjustments to work with the new hardware. For example, we could not boot Windows 10 on Arm like we did with the Pi 3B +.
Key Differences
The table below shows a comparison of key specifications between the Raspberry Pi 4B (the first and only Pi 4 model) and the Raspberry Pi 3B + (the fastest version of the Pi 3).
| Specification | 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) |
| Memory | 1 – 4GB DDR4 | 1GB DDR2 |
| GPU | 500 MHz VideoCore VI | 400 MHz VideoCore IV |
| Video Output | 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 |
| Power Port | USB Type-C | Micro USB |
| Power Requirements | 3A, 5V | 2.5A, 5V |
| Dimensions | 3.5 x 2.3 x 0.76 inches (88 x 58 x 19.5 mm) | 3.2 x 2.2 x 0.76 inches (82 x 56 x 19.5 mm) |
| Weight | 0.1 lbs (46 g) | 0.11 lbs (50 g) |
The most significant new features are a faster processor and GPU, more and faster RAM, increased USB 3 ports, dual micro HDMI ports instead of a single HDMI connection, and support for 4K output. The higher bus speeds enabled by USB 3 also allow the onboard Ethernet port to support true gigabit connections (125MBps), whereas the theoretical maximum of the last generation was only 41MBps. The speed of the microSD card slot is also doubled from the original’s theoretical maximum of 25MBps to 50MBps on the 3B+.
Because the new SoC requires more power, the Raspberry Pi 4B is powered via USB Type-C instead of micro USB. It also requires a power adapter capable of supplying at least 3 amps and 5 volts, but if you do not have many peripherals connected to the USB ports, you can use 2.5 amps. Setting aside power requirements, the USB Type-C connector is reversible, making it easier for children (and adults) to plug in.
Design
The Pi 4 measures 3.5 x 2.3 x 0.76 inches (88 x 58 x 19.5 mm) and weighs 0.1 lbs (46 g), making it thin enough to fit in a pocket and lightweight for portability. The board is durable enough to roll around in your bag, but we recommend sticking it in something protective mainly to protect the pins. However, during testing, I always left it bare on my desk, moving it back and forth between work and home multiple times, simply putting it in a cardboard box without padding or anti-static bags.
Unfortunately, if you want a case, you cannot use cases designed for any previous Raspberry Pi. The Raspberry Pi 3B/3B+ has nearly the same dimensions, but the port layout has changed enough to make the Pi4B incompatible. While previous Pis had a single full-size HDMI port, the dual micro HDMI connectors on the Pi4 protrude more, so they do not align with the holes on anything designed for the Pi3B.
The Raspberry Pi 4 covers more than just the basics of porting. There are four USB Type-A connections on the right side, two of which are USB 3.0. There is also a full-size gigabit Ethernet port for wired connections. The bottom edge has a 3.5mm audio jack, two micro HDMI ports, and a USB Type-C power port. On the left side, you will find the microSD card reader. On the top surface of the circuit board, you will see ribbon connectors for the camera serial interface (CSI) and display serial interface (DSI), which provide dedicated connections to Raspberry Pi’s own cameras and screens (or compatible accessories). Of course, you can also connect a camera to the USB ports, as well as several common methods, including micro HDMI ports that can output to a display.
New CPU, RAM
The Raspberry Pi 4 retains a similar design and dimensions to its predecessors, but it is a whole new platform powered by the new Broadcom BCM2711B0 processor. Since the first Pi launched in 2012, all Pis have used a 40nm SoC, but this new chip is based on a 28nm process, and instead of the old Cortex-A53 microarchitecture, it uses Cortex-A72. The BCM2711B0 in the Raspberry Pi 4 has four cores with a clock speed of 1.5 GHz, and at first glance, it does not seem much faster than the four-core 1.4 GHz BCM2837B0 in the Raspberry Pi 3B +.
However, the Cortex A72 has a 15-instruction pipeline depth, while the older model has only 8, and it also provides out-of-order execution, so it does not wait for one process to output before starting another. Therefore, even at the same clock speed (and the BCM2711B0 being based on a smaller process node), the Cortex-A72 processor will be much faster than its A53-powered ancestors and use more power.
For example, in the Linpack benchmark test measuring overall computing power, the Pi 4 absolutely crushed the Pi 3 B + in all three tests. In the most important single-precision (SP) test, the Pi 4 scored 925, compared to the 224 of the 3 B +, an increase of 413%.
In the Sysbench CPU test, the Pi 4 B was able to execute 394 events per second, while the Pi 3 B + only managed 263 events. This is a 50% difference.
RAM is also much faster, going from 1GB DDR2 RAM running on the Pi 3B + to a maximum of 4GB DDR4 RAM. In addition to the increased bandwidth, having more memory is a huge deal, especially for web browsing.
The RAM of the Pi 4 returned read and write speeds of 4,130 and 4,427 Mbps, respectively. This is 51% and 54% better than the 3B+.
When performing file compression, both the CPU and RAM are affected. In multi-threaded mode, compressing files, the Pi4B is 37% faster than its predecessor, but it is more powerful in single-threaded mode, outperforming the 3B + by over 60%.
New GPU, Faster Graphics Performance
The GPU has also seen a significant upgrade. It transitions from the Broadcom VideoCore IV running at a core clock speed of 400MHz to the VideoCore VI set at 500MHz. The new architecture allows it to output to displays at rates of up to 4K fps at 60fps, or support dual displays at up to 4K 30Hz.
While we hoped we could try some resource-intensive emulators in Retropie for this review, there was no compatible version with the Pi4 at launch. However, the OpenArena Benchmark, which tests frame rates in Quake III Arena clone games, did run.
At 720p resolution, the Pi 4 is the only Raspberry Pi that can deliver smooth frame rates. Yes, you can game on the Pi 3, 3 A + or 3 B +, but the frame rates on all three of those machines hover between 27 and 28 fps, while the Pi 4 clocks in at 41.4 fps.
Storage Performance
No matter how fast your CPU, RAM, and GPU are, if your storage speed is slow, opening applications and files and other everyday tasks will be very laggy. As with all Raspberry Pis, the primary storage device for the 4B is the microSD card reader, which, while convenient, is somewhat limited. According to the Pi Foundation, the maximum transfer rate for the 4B is 50MBps, which is double the speed of the 3B+ reader. There is no known capacity limit.
Our benchmarks were conducted using a Samsung EVO Plus microSD XC Class 10 card, which showed less impressive speeds than the theoretical maximum. The sequential read/write speeds of the Pi 4B were 45.7 and 27.7MBps, while the 3B+ marked 22.8 and 17.5MBps. Please note that the card is rated for read speeds of 100MBps and write speeds of 60MBps.
If you have a fast USB flash drive or external SSD, you can get better storage performance from the Pi4B. The Pi4B is the first to have USB3 ports, with a maximum theoretical bandwidth of 625MBps.
By connecting a Mushkin 120GB external SSD to one of the USB3 ports, the Pi4B achieved impressive read and write transfer rates of 363 and 323MBps, respectively. This is nearly ten times faster than the 34MBps mark of the 3, 3B, and 3B+.
The fast USB3 ports are not just for storage. You can use other high-bandwidth peripherals, such as Google’s Coral USB Accelerator, which can help complete AI tasks.
Network Performance
The Raspberry Pi 4 has the same 802.11ac Wi-Fi as its predecessors, but it supports Bluetooth 5.0, which is an improvement over the previous model’s Bluetooth 4. More importantly, the Ethernet port now has more bandwidth, allowing it to deliver full gigabit throughput, whereas previous models maxed out at around 330 megabits.
In testing, the Ethernet port of the PI4B reached 943Mbps, blowing away other Raspberry Pis. In fact, in throughput tests, the Pi4B’s rate was 943Mbps (close to the maximum of 1,000Mbps). This is nearly five times that of the Pi3B+, which only managed 237 Mbps.
Both old and new Raspberry Pis have 802.11ac Wi-Fi, which can operate on either the 2.4GHz or 5GHz bands. So we did not expect to see a significant performance difference here. But the Pi4’s 5GHz throughput is noticeably higher, returning a rate of 114Mbps, while the Pi3B+ achieved 97Mbps, representing an 18% improvement.
Power and Heat
Due to the more power-hungry processor and the need for at least a 5-volt, 3-amp power adapter, the Pi4 is expected to consume more power than its predecessors.
At idle, the Pi 4B consumes 3.4 watts, 17% higher than the 3B+, while under load, that number jumps to 7.6 watts, but this is still 19% more than its predecessor. If you want the lowest power Pi, performance will be affected, so go for the Pi Zero W, which consumes only 0.8 watts at idle and 1.6 watts under load.
Yes, this board runs warmer than the previous one. Thermal images reflect what we experienced; the area of the board near the CPU is very warm, not just the top of the processor itself. The Pi4 board reached 74.5 degrees Celsius (166 degrees Fahrenheit). This is not hot enough for serious burns, but children should especially be sure to only pick up the Pi by its sides. The top surface of the Pi3B+ was cooler, with a maximum temperature of 62.5 degrees Celsius (144.6 degrees Fahrenheit).
Thermal image of Raspberry Pi3B+ (Image source: Gareth Halfacree)
Thermal image of Raspberry Pi4B (Image source: Gareth Halfacree)
As with any modern computer, if you push the system too hard and the CPU or GPU overheats, the computer will throttle to avoid damage.
When running a CPU-intensive workload for 10 minutes, the processor reached 81 degrees and began throttling from 1.5 GHz down to 1 GHz after 3 minutes. However, once the system drops to around 80 degrees, it still recovers to 1.5GHz fully, but then it warms up again and drops down to 1GHz. If you want better sustained performance under load, consider installing an active cooler for the Raspberry Pi4, or at least a passive heatsink.
GPIO Pins
The real star of any Raspberry Pi is its 40 GPIO (general-purpose input/output) pins. The number and layout of the pins remain unchanged from previous models, going back to the Raspberry Pi 2, so any “hats,” sensors, or LED screens connected to the Pi 2 or 3 are compatible.
(Image source: Gareth Halfacree)
However, the Raspberry Pi 4 adds some new functionality to some of the pins. For hardcore makers connecting various peripherals, the GPIO pins now support four additional I2C, SPI, and UART connections. So if your sensors or peripherals require any of these interfaces, you now have more of those available.
On the Raspberry Pi 4, the GPIO pins are also much faster and more responsive, likely due to its faster processor. Our tests using the gpiozero Python library continuously turned the pins on and off and measured the rate at which they switched. The Pi 4 clocked in at 50.8 KHz, while the Pi 3 B + only managed 16.1. This is a 215% improvement.
Using Raspberry Pi 4 as a PC
One of the goals of the Raspberry Pi 4 is to serve as a powerful PC that anyone can use for web browsing, light productivity work, and even playing very basic games. To test this use case, I spent several hours doing daily work on the device, even using it to write part of this review.
I really enjoyed being able to output to dual displays, which is something I do every day at work and home. And since most of my daily work is done in a web browser, writing, editing, and researching articles using Chromium was no problem. Even with 15 tabs open, switching between them was smooth, and I did not max out the 4GB of onboard RAM.
While I wouldn’t want to use it every day, GIMP provides a way to edit static images. If I wanted to crunch a spreadsheet or write a document outside of Google Docs, Libre Office would suffice.
My biggest issue revolved around video playback. If I wanted to watch a YouTube video, I had to keep it in a window because even at 480p resolution, it was choppy in fullscreen. Another task I wanted to perform was playing retro games, but at the time of writing, the Retropie emulator package was not compatible with the Pi 4. However, I was able to install and play Quake Arena.Keep in mind that the Raspberry Pi 4 can work with several different operating systems, but the most supported is Raspbian, a Linux that has a small learning curve for newcomers. Users looking for a low-cost web-surfing computer without any modifications can purchase a Chromebook or low-end Windows laptop for $150 to $200.
4K Output, Video Playback, and Transcoding
One of the drawbacks of previous Raspberry Pi computers was that they could only natively output to one screen at a time, but if you like multitasking and want to use the Pi to increase your productivity, you really need a second screen. The Raspberry Pi 4 has dual micro HDMI ports, each of which can connect to a separate display or TV and can run at resolutions of up to 4K (3840 x 2160). If you have multiple 4K displays, you have a choice: you can run each screen at 30 Hz, or you can enable 4K mode in the settings menu, which raises the voltage slightly, allowing you to run one display at 4K 60 Hz and another at up to 1080p.
In extensive hands-on testing, I found that while 30 Hz 4K is tolerable, small things like moving the mouse pointer can feel a little sluggish. If you have a 4K screen, you are better off choosing the 60 Hz mode, but be aware that the increased voltage can also cause the CPU to heat up and throttle more easily.
Browsing the web, viewing static images, and just enjoying all the extra screen space of 4K is fantastic, but video playback is the Achilles’ heel of the Raspberry Pi 4, at least at the time of writing. Whether we tried streaming 4K video or using downloaded files, we could not achieve a smooth, workable 4K experience on Raspbian Buster or the operating system running the Kodi media player, LibreElec. Several H.264 encoded videos, including Tears of Steel, simply would not play or displayed as garbled colors. Even Kodi’s recommended sample jellyfish video displayed as a still image without movement. Clearly, there is still a lot of optimization needed on the operating system and software side to make the Raspberry Pi 4 capable of playing 4K video.
Unfortunately, even playing 1080p YouTube videos was a challenge. Running at 1080p resolution, the full-screen trailer for Stranger Things showed noticeable choppiness. However, when I watched the same clip in a smaller window, it played smoothly. Even when I lowered the stream’s resolution to 480p, the same issues persisted.
If your screen resolution is 1920 x 1080 or lower, playing offline 1080p videos works great. When I watched the downloaded trailer for Avenger’s Endgame using VLC player, it was very smooth.
The Raspberry Pi 4 will not replace anyone’s MacBook Pro or Dell XPS 13 creative workstation, but if you have patience, it can transcode video for you. Using FFmpeg, the Raspberry Pi 4 transcoded a very short H.264 encoded clip to NTSC DV format in 48 seconds. This is much less time than the Pi 3 B + took, which completed it in 108 seconds, but if you want to convert a full movie, you might need to leave your Pi for a while and come back.
Web Surfing
The web surfing experience on the Raspberry Pi 4 is noticeably smoother than any of its predecessors. The faster processor helps, but having over 1GB of RAM does too. I noticed in the Gnome System Monitor that I was using over 1GB of RAM even with one or two tabs open. However, on the Pi 4 with 4GB of RAM, I had no issues running over 15 tabs at once and switching between them.
While web page rendering is not as fast as modern Core i7 laptops running Windows 10, the Pi 4 provides a very reliable web browsing experience. I encountered no issues when using Google suite applications, including Gmail, Google Sheets, and Google Docs.
In Jetstream 1.1, a comprehensive web benchmark test that measures Javascript processing and page rendering, the Pi 4 beat the Pi 3B+ 42.5 to 17.1, which is a 148% improvement, but the Pi is still not as powerful as low-end Intel-supported Chromebooks like the Samsung Chromebook 3, which scored 49.7. However, PC laptops performed worse, including the Dell Inspiron 14 3000, which only scored 35.9.
Speedometer 2.0 benchmark measures overall responsiveness by loading virtual web applications and then simulating user interactions with them. The higher the score for this test, the less latency you should experience when actually using web tools like Google Docs or Gmail. Similar to Jetstream and in real-world scenarios, the Pi 4 leads its predecessor. In this case, it was 98% faster.
Forget about using websites with webGL animations, as they are slideshows at least with the current software. When I launched the webGL aquarium demo showing 50 fish swimming, I was only getting 2 fps on the Raspberry Pi 4, while on the Pi 3 B + I only got 1 fps. I thought this would double the speed of the Pi 4, but 2 fps is still useless.
Virtual Hosting
Web services are one of the most common use cases for the Raspberry Pi. In fact, at Tom’s Hardware, we use the Raspberry Pi 3 B as our local network server for hosting our notebook battery tests. The Raspberry Pi 4, with its faster processor, larger RAM, and better network connectivity, promises to deliver more powerful web surfing.
Using the Phoronix Apache test, the Raspberry Pi 4 processes 3,983 requests per second, while the Pi 3 B + processes 2,850 requests. This is a 40% improvement, meaning you can serve heavier web pages or serve more visitors simultaneously without lag.
Many web applications use PHP server-side scripting language, so processing PHP faster can help a lot. In measuring PHP performance on PHPBench, the Raspberry Pi 4 B scored 101,540, more than double the 41,351 of the Pi 3 B +.
AI, Inference, and Machine Learning
Perhaps the most exciting new use case for the Raspberry Pi 4 is for inference and machine learning. With earlier Pis, you could perform simple object detection at low frame rates using a camera, but the increased performance and I/O of this new model should open up a whole new world of use cases.
To understand how the Pi 4 handles object detection, we followed the steps in this tutorial that uses a combination of Google’s TensorFlow machine learning platform and OpenCV, a programming library that facilitates computer vision. After spending three hours compiling and installing all the software, I let the application run and watched as the webcam recognized a few (very few) objects, including thinking I was a “person” and my chair being a confidently “chair.” It ran at a low speed of 1.7 fps, but that’s 70% better than when running on the Pi 3 B + at 1 fps.
However, with more optimized frameworks, the Pi 4 should be capable of real-time face and object recognition. And because it has USB 3, accelerators like the Google Coral TPU USB dongle should have more bandwidth to send data back to the SoC. Imagine building a home companion robot that recognizes each member of the family by face or helping farmers classify cucumbers by type. Some of these workloads could be achieved on earlier Raspberry Pi computers, but the Pi 4 B should make them fast and accurate enough for regular use. We can’t wait to see what developers and manufacturers do with the Pi 4 and AI.
Scikit-learn is a popular Python module that implements machine learning. Performing Scikit-learn tasks on the Pi 4 B is more than twice as fast as on the Pi 4 B.
Compiling Code
With Linux, sometimes you have to compile programs to install. During our testing, we had to compile packages multiple times, including when we wanted to get the object recognition demo.
The faster processor and better RAM help the Raspberry Pi 4 B compile code faster than its predecessor. When we ran tests compiling the Linux kernel, the 4 B was 33% faster. So whether you are a developer writing your software or just a user wanting programs to download directly, the Pi 4 can save you time.
Overclocking the Pi 4
We have explained how to overclock the Raspberry Pi 4 and what kind of results you get in a separate article. However, the most important thing is that you can easily boost the 1.5 GHz CPU up to 1.75 GHz and raise the GPU frequency from 500 to 600 MHz without missing a beat. Just make sure you have cooling.
How Much RAM Do You Need for Raspberry Pi 4?
The Raspberry Pi 4 B comes in three configurations, all the same except for the amount of RAM. The $35 entry-level model has 1GB of memory, the $45 unit has 2GB, and the $55 SKU goes up to 4GB. One of the big advantages of all Raspberry Pis is that they are affordable and can be used for just about anything, so you need to choose wisely. If you are building a robot or other IoT device that only handles motors and sensors, 1GB is sufficient because you are not running many applications and don’t even need a GUI.
If you are doing very light web surfing, setting up a self-service terminal, or deploying a limited-use web server, we recommend using 2GB. The 4GB model is excellent for using the Pi as a PC or for more complex tasks (like AI).
Conclusion
The Raspberry Pi 4 represents a huge leap forward, not just for the Raspberry Pi but for single-board computing. It is now realistic to use the Pi as a secondary PC or backup PC (or perhaps a child’s first PC). However, the real benefit comes not from those using Raspberry Pi 4s in place of x86 PCs, but from all the innovators who will leverage the system’s enhanced performance, I/O, and graphics to create new IoT devices, media servers, and robots. Kids building Pi projects in schools will also have a whole new learning opportunity.
However, if you need a Raspberry Pi computer today, you will have to endure some issues that may be resolved in the near future through software updates. Key applications like Retropie do not work on the Raspberry Pi 4, and video playback performance is disappointing. While it is certain that major applications will be ported to the new computer, we still do not know how good video playback will be once the operating system improves over time.
Despite these small issues, the Pi 4 still leads its predecessors and all other low-cost single-board computers on the market. The main question is not: What can the Pi 4 do for you, but what can you do with it?
Editor’s Note: Some of the benchmarks in this article were conducted by co-author Gareth Halfacree, who published his own detailed analysis of Raspberry Pi 4 performance on Medium (https://medium.com/@ghalfacree/benchmarking-the-raspberry-pi-4-73e5afbcd54b).