Why you need a Raspberry Pi

The current king of the Raspberry Pi board offerings: the Model 4B (credit)

I wasn’t originally planning on getting an upgrade. My old Raspberry Pi Model 3B was a little old, sure, but it still had a reasonable amount of grunt. But it had seen better days. But since I’ve been rediscovering my creative side – I’m finding it a bit lacking.

I’d bent two of the pins which made getting accessories on and off it a pain. The power lead I had wouldn’t always stay in as I’d broken off one of the clips. And the micro SD card slot was what could charitable be called ‘loose’. I’ve been developing code straight on the device instead of porting it from my desktop to the Pi and back and it’s just a tad too slow at doing basic things like opening windows and copying files.

So I started reading up on what the latest offering from the Raspberry Pi Foundation was and what it could do.

Raspberry Pi who?

But let’s step back a minute. What is a Raspberry Pi and why do you need one?

The Raspberry Pi is a small credit card sized computer, designed and built by the Raspberry Pi Foundation. It’s based mostly on the same processors and technology that you would find in a modern mobile phone but has some exciting additional hardware such as USB ports, HDMI outputs, built in wireless connectivity and perhaps most importantly GPIO (General Purpose Input / Output) pins that allows it to control a range of electronic devices from LEDs to radio transmitters to motors to cameras.

Along with this hardware, you can run a number of operating systems on their boards including the recommended Raspberry Pi OS, as well as Ubuntu, Android and even a very lightweight version of Windows! The recommended programming language for a Raspberry Pi is Python but all sorts of code and languages can be run on the thing.

If you (or perhaps a relative) have even the slightest interest in computers, programming, electronics or robotics and you don’t own one – I really think you need to try one out. The capacity to wire up your own hardware and program your own software in one little (cheap!) package is truly astounding and I only wish I’d had the option when I was 12 years old and messing around with the family’s bulky beige horrible Dell desktop computer.

But which one should you get? And how much is it?

My (current) Raspberry Pi board collection. That Model 1B is an original run one from 2012!

If you look at their current products page, I believe there are 9(!) models available to purchase. Every new generation has brought more powerful and efficient CPU cores and board features at roughly the same £35 price for the xB model so my general advice if you are brand new to the Raspberry Pi family is to buy the latest Model B variant which right now is the same Model 4B that I purchased a few days ago.

A Model 3B+ (the + is important and a distinct model from the Model 3B) would also be a reasonable choice as while it lacks some of the newer features on the Model 4B, it is a tried and tested design and is capable of great things at low power consumption.

The final recommendation is for a Zero W or Zero WH (the WH has the GPIO pins soldered on already, the W does not) where you need minimal processing power and low energy usage is a requirement. Something like a remote battery powered weather station could be a good idea for one of these. I would however avoid these until you’ve mastered building and programming on a Model 3B+ or Model 4B first as these things are slow in comparison.

If you’d like to use a Raspberry Pi roughly as a desktop replacement – such as browsing the web, writing code on the board itself or playing Minecraft on it (it comes included for free!) then I would recommend the cheapest 2GB RAM version. If your interests are more AI training, video transcoding or large databases with caching then I probably don’t need to tell you that the 4GB or 8GB RAM versions are probably more up your street. I personally went for the 4GB version for a little bit of future-proofing and because I don’t expect to upgrade for a while.

Comparing the specifications

I’ve compiled a nice little table below which summarises the major differences (with a Model 3B as I don’t own a Model 3B+).

Model 4BModel 3BZero W(H)
CPU Cores4x Cortex A-72
@ 1.5 Ghz
4x Cortex A-53
@ 1.2 Ghz
1x ARM1176JZF
@ 1 Ghz
RAM2 / 4 / 8 GB DDR4 (!)1 GB DDR2512 MB DDR2
GPUVideoCore VI
@ 500 Mhz
VideoCore IV
@ 250 Mhz
VideoCore IV
@ 250 Mhz
USB Ports2x USB 3.0 (!)
2x USB 2.0
4x USB 2.01x USB 2.0
(micro USB)
Video Output2x micro-HDMI
(up to 4K(!))
1x HDMI
(up to 1080p)
1x mini-HDMI
(up to 1080p)
Wi-Fib/g/n/ac dual band
2.4/5.0 Ghz
b/g/n 2.4 Ghzb/g/n 2.4 Ghz
Bluetooth5.0(!)4.1 BLE4.1 BLE
Ethernet1 Gb/s (!)100 Mb/sN/A
Supported storagemicroSD card
Boot from SSD
microSD card
Boot from SSD
microSD card
Price~£35 (2GB)
~£55 (4GB)
~£75 (8GB)
~£32~£9.30 (w/o headers)
~£13.50 (/w headers)
The highlights of each member of the Raspberry Pi family I would recommend

You can see why I would recommend the Model 4B over the Model 3B and why I felt it was time for an upgrade. The CPU cores are much faster (more on this in a minute), the GPU is faster, there is support for USB 3.0 speeds (woohoo!) as well as better Wi-Fi speeds, better Bluetooth support, double the RAM and up to 10x the wired internet connection speeds and all for the same £35 price I paid back in 2016!

Ain’t technological process grand eh? I even took the liberty of bench-marking the above boards against each other to show just how much powerful each of them are. Bare in mind that the Zero W(H) has the same processor in it as the original Model 1B I purchased way back in 2012, which again cost £35 at the time.

I ran the below command on each Raspberry Pi, with a Pimoroni Fan Shim attached which helps cool the boards down and extract maximum performance from them. This is solely to test the single core performance of each board as the Zero W(H) does not have four cores like the other two models.

sysbench --test=cpu --cpu-max-prime=25000 --num-threads=1 run

This does a simple calculation on the CPU that works out all the prime numbers from 1 to 25,000 and records the time taken and the average numbers considered per second.

As you can see from my results above, the Raspberry Pi Model 4B absolutely creams its predecessor the Model 3B. The Zero W(H) with its very old CPU core architecture never stood a chance. In fact, on a normalised run where both run at 1 Ghz clock speed, the Model 4B is 66% faster than the Zero W(H)!

And finally comparing the full power of both the Model 3B and Model 4B, I put them in a head to head with all four cores blazing to see what the result would be, using the below command.

sysbench --test=cpu --cpu-max-prime=25000 --num-threads=4 run

Incredibly, the Model 4B is a whole 18 degrees cooler when running (with a fan) which goes to show just how more efficient its cores are. At full tilt it is also delivering 50% more performance than the Model 3B. If you can’t tell, I had a lot of fun comparing these boards to each other to validate them!

How much does all this cost to setup?

On top of the actual Raspberry Pi itself, you will need a few additional items to get up and running. Some are optional, like my SSD below. I’ve compiled a list of recommended parts to get you started and some optional extras at the bottom. I’m assuming you have a keyboard, mouse and monitor / TV you can use already.

My current setup for the new Raspberry Pi Model 4B with external SSD
  • Raspberry Pi Model 4B (£35 / £55 / £75)
  • USB-C Power Supply (£7.50) or any recent USB-C mobile phone charger
  • A micro-HDMI to HDMI dongle (£3.60) or direct micro-HDMI to HDMI cable (£5.10)
  • A case to protect your Pi is recommended (£6.00)
  • A microSD card, ideally 16 GB or greater (32 GB: £9.00)

Total: £53.60 to £82.60

If you are feeling adventurous and wish to push your Pi to its limits then the following would also be highly recommended:

  • An excellent quality 120 GB solid state drive (£20.39)
  • A SATA to USB 3.0 adapter for your SSD (£6.00)
  • A fan to keep your Pi cool and running fast (£9.90)

That’s very cool but what can I do with it?

My recent delivery containing what I needed to get my new Raspberry Pi up and running (clockwise from top-left: case, power supply, micro-HDMI dongle, Raspberry Pi Model 4B)

The short answer is, whatever you can think of! There’s a huge community out there sharing ideas, projects and the latest quirks they’ve found with their boards. I am personally looking into building my own home automation kit – smart lights, smart switches, a more intelligent charger for my car and my wife’s incoming electric moped. I’m even toying with designing and programming my own smart thermostat. Partially for the learning experience but also because I don’t want to have to sign up to another bloody account and have all my data sitting on someone else’s server – and them charging me a subscription fee for the privilege! But that rant is for another day.

You don’t have to be like me to enjoy tinkering with things – sometimes it’s just cool to own a unique piece of technology and let someone else sort out all that faff and just download and run cool things on your own custom little computer…!

Let me know in the comments if there’s any other tinkerers lurking out here and what sort of projects you’ve come up with!