A new version of the Raspberry Pi computer goes on sale today - boosting the credit card-sized board's processing power and adding wi-fi support.
The Raspberry Pi 3, available for $35, can carry out most tasks about 50 percent faster than the Raspberry Pi 2.
The Pi 3 is the second major upgrade to the board in just over a year, with the Raspberry Pi 2 only released in February last year.
The board's co-creator Eben Upton says the new $35 machine can more comfortably handle web browsing and office tasks demanded by home users.
"We've got a 10x improvement in processing in 13 months," said Upton, describing the jump from the single core processor of the original Pi to a faster, more capable quad-core chipset in the Pi 3. The Pi 3 is based on a 64-bit chipset that also runs faster than the Pi 2's 900MHz quad-core, 32-bit ARM Cortex-A7-based hardware.
"Talking to people who've played with the units, it's crossed some kind of line," he said.
"It's become more PC-like. When you're using LibreOffice and the web browser it just feels more modern in that respect.
"You're looking at an entry-level PC from the latter part of the last decade."
Breaking down the performance, the Raspberry Pi 3's new CPU performs 50-60 percent faster in 32-bit mode than that of the Raspberry Pi 2 and roughly ten times better than the original single-core Raspberry Pi in a multi-threaded CPU benchmark like SysBench. Compared to the original Pi, real world applications will see a performance increase of between 2.5x - for single-threaded applications - and more than 20x - for NEON-enabled video codecs.
A bonus for people running a Pi as a media center is the new board can play 1080p video at 60 frames per second.
The addition of wi-fi and Bluetooth support - a first for the Pi - should make it easier to get online and to add peripherals.
The previous generation Raspberry Pi boards will continue to be sold after the Pi 3's release, although Upton says there is limited scope to reduce the cost of Raspberry Pi 2 Model B due to the chipset not being "significantly more cost effective" than that of the Raspberry Pi 3.
The Pi 3 Model B that goes on sale on today will be followed by the release of the Raspberry Pi 3 Compute Model - a few months from now - and the Pi 3 Model A, which will release in the middle of this year. Versions of the compute module and Model A based on the Raspberry Pi 2 will not be released.
The compute module packs the processor and memory of the Pi onto a slim board the size of a memory module. The idea of the compute board is to make it easier to bolt together a custom appliance using a Pi, as the compute module can be plugged into a base board with all of the necessary peripheral circuitry.
The Pi 3 Model A will have no Ethernet and only one USB port but sell for a cheaper price. In the Pi 3, however, Upton says the lack of Ethernet and single USB will be compensated for by wi-fi and Bluetooth connectivity.
The foundation doesn't plan to release a new board every year, with Upton saying the short gap between the launch of the Pi 2 and Pi 3 is a one-off - made possible by a combination of technical and cost factors.
"We're kind of at the end of that particular roadmap. I would expect a longer pause, a couple of years at least, before any kind of major bump to the platform," he said.
It also coincides with the Raspberry Pi Foundation shipping more than eight million boards and the fourth anniversary of the Raspberry Pi's launch.
Getting hold of a Pi 3 should be easier than was the case for previous generation boards, as Upton says there will be a much more steady supply.
"This year we have a much more robust supply chain. There will be 100,000 flowing through every week for as long as we need, to deal with the demand that's built up."
He still cautions that, given the spike in sales that follows each major new release of the Pi, he expects "supply will be fairly tight for the first few days".
What's new and what's not
Add-ons for earlier Pi boards should still work as the dimensions and layout of the board remain the same, apart from the LEDs moving position. Consequently these LEDs won't be visible on some cases for previous generations of the Pi and a new official case will be released.
Peak power consumption of the Pi 3 is about 50 - 60 percent higher than its predecessors, though Upton says that "power consumption at constant workload stays the same". Alongside the Pi 3 will be the launch of a new official power supply, which will be rated at 2.5A5.1V, compared to the 2A5V-rated supply used by earlier boards.
Unlike previous boards, the Pi 3 will be able to boot directly from a USB-attached hard or pen drive - rather than having to boot from an SD card. Similarly Pi 3 will also support booting from a network-attached file system, using PXE, without the need for boot data on an SD card.
Photos of the Raspberry Pi through the ages: From the prototype to Pi 3 B+
The addition of this wireless connectivity also reduces the chance of bottlenecking the board. A gripe about earlier models of the Pi is that USB and Ethernet share the same data bus. This shared bus limits the data that can be passed to and from the Pi. Consequently when a user attempts to simultaneously pass large amounts of data over Ethernet and to a USB-attached device, say storage, data transfer rates can bog down.
The Pi 3's wireless LAN doesn't share the USB bus - lessening the constraints on network connectivity.
One much requested feature that Upton says has been omitted from the Pi 3 is the addition of a Sata port, which would provide a high speed connection for attaching storage. He explains the Pi 3's technical constraints would have limited a Sata port, as it would have had to have shared the USB2 bus - effectively throttling its maximum throughput of 6 Gbps down to the 480 Mbps speed of USB2.