Connect with us

Serious Hardware

Raspberry PI, the world’s cheapest computer

A frenzied response to Raspberry PI, a $25 computer the size of a credit card, meant it sold out within hours of its release on Wednesday. PHILIP MACHANICK of the Department of Computer Science at Rhodes University explains its significance.

Raspberry PI, a single-board computer the size of a credit card, launched on 29 February after many months of anticipation and slippage of the originally planned late 2011 release. The web servers of suppliers melted down within seconds of the announcement, and #Raspberry_Pi rapidly trended to the top of Twitter.

Why would something as apparently mundane as a logic board with no case, no mouse, no keyboard, no disk, no power supply and no screen create so much enthusiasm?

Try this: $35.

And that’s the fancier model. It starts at $25, if you don’t need ethernet.

The parts it’s based on are cell phone technology: an ARM processor, with 256MB of RAM that takes up minimal space, so the total size of the logic board is very small, with a minimal number of components.

The 700MHz ARM chip runs at about the speed of a 300MHz Pentium II. On the other hand it has a relatively powerful graphics unit that can play full 1080p HD movies and run 3D games pretty well.

The cost is so low because of very careful minimalist design (it doesn’t even have an onboard realtime clock since remembering the time and date requires a battery, a significant cost with such a tight budget), and because the basic parts derive from the massive volumes in the cell phone market.

At launch, there are two models: Model A lacks ethernet and has only one USB port: Model B has ethernet and a second USB port. Both have 256MB of (non-upgradable) RAM. By the start of the British school year later in 2012, Model A will include a case, and kits with some of the missing parts will be available for those who want a whole computer.

Raspberry Pi is designed by a charitable foundation in the United Kingdom with the aim of bringing sophisticated computing to children, so something closer to real computer science can be taught in schools. I am personally a little skeptical of whether technology can solve the problem of teachers lacking the skills to do teach meaningful, deep, technical computer skills, but a really cheap computing platform is great news for Africa.

In addition to the board, you need a flash SD card as a boot disk. You can plug in a standard USB mouse and keyboard, and the board can either take a modern HDMI screen (including most digital TVs) or an analogue TV. For power, you need a 5V power supply that connects through a micro USB port, fast becoming the standard for cell phone chargers.

This means that African entrepreneurs, educators and researchers can set up shop at a fraction of the price of buying a conventional computer.

What’s more, the platform is fully based on free software (except a chunk of code needed to drive the graphics that comes from the chip set designer, Broadcom). That means the cost of getting started is pretty much the only cost aside from electricity and possibly networking. Despite its tiny size, it’s a fully-fledged computer, and can do any traditional computing task from word processing to software development. You could even use one as small-scale file or web server.

In addition to low cost, the Raspberry Pi uses very little power: only 3.5W. That means you could run one in a place with dodgy power off an inexpensive UPS for hours, instead of the 10-15 minutes you’d expect a conventional PC to keep going before the battery ran down.

So is this a significant development, or an interesting toy with a few niches where it will do well?

I see this as a really big game changer, in the same way as the personal computer was in the 1970s and ’80s.

The first personal computers were hobbyists toys, some assembly required. The first computer that broke out of that niche, with a nice case and robust enough design for entry-level business use, was the Apple II, which started out at about $1300.

Put the Raspberry Pi in a nice case (as is planned for later in the year) and you have something that’s a lot more capable than an Apple II for less than 3% of the price. The evolution of Linux as a reliable, highly usable operating system puts a new device like this far ahead of the rickety personal computers of prehistory.

If I were Apple, Microsoft or Dell, I’d be worried.

Where to buy

In South Africa, Raspberry Pi Model B was intended to be on sale from RS Components at R259.20. However, it is not showing as available to order at time of writing – possibly due to a little matter of being sold out. But still, that price is amazingly close to the international price of $35.

For more information, visit


Subscribe to our free newsletter
Continue Reading
You may also like...
To Top