Raspberry Pi 4 Delivers Notable Performance Improvements Amid Software Issues
The Raspberry Pi 4 Is Better, Faster, Stronger with Revamped I/O and More Memory
The Raspberry Pi Foundation recently launched its latest budget-friendly single board computer dubbed the Raspberry Pi 4 Model B. Offered in three RAM configurations of 1GB, 2GB, and 4GB of LDPPDR4-3200 memory, the base Raspberry Pi 4 comes in at the same $35 price point of its predecessor while the 2GB sits at $45 and the 4GB model is priced at $55. Featuring a faster SoC, dual display outputs, and faster storage, networking, and USB I/O –thanks to dedicated links to the SoC – the Pi 4 represents a notable performance upgrade over 2018’s Pi 3+ SBCs while maintaining compatibility with GPIO, CSI (camera), and DSI (display) connected devices. Because the USB and Ethernet ports have swapped places, the display outputs have changed, and the ports all stick out an extra 1mm to sit more flush with cases you may need a new case even though the Pi 4 is a similar 85x65x19.5mm form factor if you plan to upgrade.
Speaking of I/O, the Raspberry Pi 4 Model B offers up a single Gigabit Ethernet port, two USB 3.0 ports, two USB 2.0 ports, one 3.5mm audio and composite video output, two Micro HDMI video outputs, a USB-C power connector (15W/3A), a single MicroSD card slot on the underside, and the usual complement of 40-pin GPIO, CSI, and DSI headers. There is even Power over Ethernet (POE) support with a compatible HAT accessory.
On the surface, the I/O has not changed that much, but thanks to better internal hardware, the I/O is much faster. There is now native Gigabit Ethernet support (previous Raspberry Pis maxed out a bit over 300 Mbps) and thanks to a dedicated VLI controller running on a PCI-E 2.0 x1 link, USB devices have up to 4 Gbps of bandwidth to share. Even the microSD card slot has been upgraded to support up to 50 MB/s versus 25 MB/s on the Pi 3 B+ though enthusiast may opt to use USB storage after a future update will add the ability to boot from a USB connected device which should make using the Pi as a cheap desktop replacement a much smoother experience. The wireless networking chipset (a Broadcom PHY connected to the SoC via RGMII link) handling 802.11ac has not changed, but a software update brings newer Bluetooth 5.0 and BLE (Bluetooth low energy) support and reviewers have found the Pi 4 offering up faster 5 GHz performance versus the Pi 3 models. GPIO pinout is backwards compatible, but there are extra connections for I2C, SPI, or UART.
Sitting at the heart of the Raspberry Pi 4 Model B is a 28nm Broadcom BCM2711 SoC with a quad core ARM Cortex A-72 CPU clocked at 1.5 GHz (moving to Out of Order Execution with longer (15 versus 8) instruction pipeline) and a VideoCore VI GPU clocked at 500 MHz that reportedly supports OpenGL ES 1.1/2/3, H.265 4k60 and H.264 1080p60 decode (H.264 1080p30 encode), and dual 4K display outputs (one display at 4k60, one monitor at 4k30 plus one 1080p60, or two at 4k 30Hz out of the box, or two at 4k 60Hz if you are willing to overclock the GPU).
Performance from initial reviews appears to be fairly good with software support (no Windows on ARM or RetroPie support currently) and video playback issues being the only major issues. The Pi 4 does also get rather hot under sustained load (up to Gareth Halfacree noted SoC temperatures up to 74.5°C) so an active cooler or at least a copper heatsink may be required if you want to ensure peak performance sans thermal throttling. The micro HDMI ports also pose a problem with such a portable device in the sense that the connectors are more fragile, but we will have to wait for longer term reviews to see how they hold up. With that said, the new processor along with extra memory (on the more expensive SKUs) should certainly speed up desktop GUI-based computing with Raspberry Pi Ltd. CEO Eben Upton stating in an interview that the new Pi 4 was up to three times faster than previous SBCs depending on the workload.
Fortunately, his claim seems to be backed up by early reviews with the new board delivering in benchmarks. While RetroPie isn’t currently working out of the box, Tom’s Hardware was able to get Quake-based OpenArena running at 720p and 41.4 FPS. Tom’s seemed to run into the most video playback issues with local 1080p video being the only thing that worked well and streaming 4K or 1080p full screen being a no-go. Youtuber Gary Explains also noticed 4K video playback issues with the stream artifacting and freezing for several seconds between frames with both H.264 and H.265 content. Gary explains that lower resolution video (480p and 1080p) local content was able to playback without issue, however. Thankfully the video playback issues may be able to at least be mitigated with future software as the hardware should be capable of it in theory. For example, Youtuber cnxlinux managed to get certain 4k30 content to play while under LibreElec although other 60 Hz clips and codecs did not work. Finally, LowSpecGamer and ETA Prime each showed that streaming video worked well in windowed mode with the latter further demonstrating the Pi struggling to stream in full screen especially for 1080p and higher resolutions. . Right now the Pi 4 seems to be very picky on which video files it likes and will playback successfully, so hopefully software updates and new GPU drivers (note that the Pi 4 and its VideoCore VI GPU uses Mesa drivers with less closed source code which is nice to see) will improve this situation.
I am interested to see the kinds of projects enthusiasts and DIYers can come up with that incorporate the new Raspberry Pi 4 and its improved hardware. Hopefully the new Debian based Raspbian Buster OS that ships with the Pi will receive quick software support and updates from the community so that the hardware is able to reach its full potential. What are your thoughts on the new SBC?