You shouldn’t buy new computers or tablets without understanding what’s inside them.
This page explains what’s inside and how it is important to how the device performs. I will explain what you need to know in order to meet my expectation (non-negotiable learning) and additional information (greater depth learning).
There are only three main things I want you to look for: Processor, Memory and Storage – all explained below.
1. Processor (or CPU).
In a nutshell: The CPU is a computer’s brain. It cannot be switched out easily, just like your brain, so choose wisely first time. This affects how quickly the computer works and an old or under-powered processor will slow the computer down.
As websites and apps get more complicated year on year (which they always do), older processors start to struggle more than younger ones.
Non-negotiable learning:
In more detail: There are lots of different processors and they run at different speeds, have more ‘cores’ and other technical advantages and disadvantages. It would be easy to get overwhelmed. So you can Google the processor name + “benchmark” to give you an idea of how fast it is. It will give you a benchmark score which you can compare with other benchmarks to see which processor is better.
There are two main companies that make processors in computers – Intel and AMD. At the most basic level, an Intel i3 (or AMD Ryzen 3) processor is fine for most primary school computers and an Intel i5 (or AMD Ryzen 5) processor will be more powerful, which might help the computer last longer. Be careful not to get a computer that contains an old processor – anything from the last two years should probably be OK but any older than that and it might struggle with modern computing requirements from the start.
I recommend: Intel i3, Intel i5, AMD Ryzen 3 or Ryzen 5 processor under 2 years old.
Greater depth learning:
CPU stands for Central Processing Unit. Every instruction travels through the processor. It works hard and gets hot, so it needs to be cooled down by its own heatsink (cooling device). In a laptop, there is less space around it for air to travel so there is usually a performance difference between the processors in laptops (lower power and heat) and desktops (higher power/heat).
You can compare processors on raw speed (measured in GHz, e.g. 1.8 GHz), but modern processors often work smarter rather than faster. For example, multiple cores (Dual-core, quad-core etc.) is like having more than one brain packed into your head. If you had four brains, you would be able to easily do four things at once. That’s the theory behind quad-core processors.
2. Memory (or RAM)
In a nutshell: Memory is like the size of your desk at work. If you have a big desk, you can be working on lots of things at the same time. Although your brain only works with one thing at a time, having a nice big desk means you can go from one thing to another quickly as it’s already laid out waiting for you. You can switch between multiple jobs easily because they’re all on your desk, ready for you.
Non-negotiable learning:
In more detail: Contrast this with if your desk were too small – you might need to work on multiple jobs but with such a small desk, you have to put job 1 away before getting the job 2 out to begin working on it. If you need to switch back to job 1, you have to put job 2 away again and get job 1 out again. Very time consuming. This is what having too little RAM feels like – your computer is slow to open things up because it’s got to get the new job out on its ‘desk’.
Computers not having enough memory is very misunderstood. It is not how much storage space you have on your computer for your files. It is a completely different part of your computer.
I recommend: I would not buy new laptops/computers with less than 8GB RAM. 4GB will get you through if that’s what you have already but will not be good enough in a few years time. 2GB or less RAM is already too little.
Greater depth learning:
RAM stands for Random Access Memory. It is much faster than a hard disk but you only have a limited amount of it. Your processor gets the job it’s working on out of storage and into RAM so that it can send information to and from RAM quickly. Once it’s finished the job, it can be ‘saved’ (i.e. sent back to storage).
If you are using a Windows PC, you can quickly and easily see how your computer’s memory is affecting your its performance. Hold the Ctrl and Shift keys down and press Esc. The Task Manager should tell you how much of your CPU and Memory are being used right now. Any more than 50% and your computer is working very hard; more than 70% and it’s struggling.
3. Storage
In a nutshell: Storage (a.k.a. hard disk space) is where all your work, files and apps are stored on your computer. It’s like the classroom store cupboard – everything goes in there waiting to be used. Just like the store cupboard, when you need to find and get something out, the time it takes depends on how well it’s organised.
Non-negotiable learning:
In more detail: There are two types of storage inside computers these days – mechanical (Hard disk or HDD) and solid state (Solid state disk or SSD).
A mechanical HDD has moving parts. You can hear the disk spinning when you turn a computer on. Solid state SSDs have no moving parts. They are silent.
Long story short: computers have had HDD for a long time. They are being phased out. An SSD uses less power and is much (up to 20 times) faster. You will notice the difference.
I recommend: You should only get computers with SSDs. 128GB is possibly enough, although 256GB is fast becoming the standard. Get a 256 GB SSD if you can.
Greater depth learning:
The difference between HDDs (that use moving parts) and SSDs (that don’t) is massive. Storing on HDD is like storing your films on VHS – it was fine when that was all we had. Storing on SSD is like watching on Netflix or iPlayer. Many orders of magnitude faster to locate, retrieve and use what you need.
HDD is only good for storing things when it doesn’t matter how long it takes to get them. So why still sell them? Well, you tend to get much more space to store your files on a mechanical HDD. If you need lots of storage space on your actual computing device, you might consider it, but it comes with a huge speed penalty. As most schools save files to a networked server, space on the actual device itself isn’t nearly as important as how quickly it starts up and opens programs.
Well done! You made it!
There are other things that you might consider that are inside a computer, but the three above are the ones that will have the biggest effect on performance.
Mastery: Only read the section below if you want to know more about how other things affect your choice of computer.
DVD drive: Sometimes called an optical drive, this can be a read only (can play DVDs) or read/write (can play or burn DVDs). Your school may have a use for DVD drives on computing equipment but they are not considered essential any more and many new laptops do not bother with one. It is possible to buy external USB DVD drives fairly cheaply.
Screen resolution: How many pixels (dots) are used to make up the display. Typically 1920 x 1080 (which is HD) or 1366 x 768 (not HD). Laptops have their own built-in monitor, so this is usually something you can check. Desktops use a separate monitor, so the computer will usually fit in with whatever the monitor’s resolution is.
Screen size: Measured in inches from top left to bottom right corner. Laptop screen size tends to give you a good indication of how big the laptop is.
Monitor: A laptop has a monitor screen built in. A desktop computer will need to connect to a monitor. Check that the desktop computer you buy has the right connections for your monitor. Monitors have mainly VGA, DVI, HDMI or DisplayPort connections. HDMI is the most common right now. If you are buying a monitor to go with your computer, check the resolution, connections and screen size are what you want.
Graphics/video card: An additional processor dedicated to graphics processing. They can be very expensive and power hungry. They are typically used for rendering complicated 3D graphics, often in games. A primary school is unlikely to have need for one and it is likely to put the price up significantly. High schools may need this in specialised machines if intensive graphics capabilities are needed.
Operating system: On a fundamental level, your computer doesn’t understand you and you don’t understand it. It only talks in 0s and 1s. Everything you do on computers relies on the operating system, designed to let you use the computer in the simplest way possible using words and pictures rather than 0s and 1s. You need an operating system. The most common are Microsoft Windows (for PCs) and MacOS (for Apple computers), neither of which is free (technically) but they often come pre-installed on new computers. There are free alternatives such as Linux and Chrome OS. Some computers are sold without operating systems to keep the cost down – talk to your IT provider to see if they are able to install Windows or another operating system before you buy.
WiFi connectivity: WiFi allows devices to connect to the school network (and subsequently the internet) without a connecting wire. Most laptops will come with WiFi connectivity. The current standard is 802.11ac (WiFi 5) which will soon be overtaken by 802.11ax (WiFi 6), but you probably won’t need to think about this. WiFi allows you to connect without cables which is very convenient but can be less stable if your WiFi network isn’t strong.
LAN/Ethernet: Many desktop computers do not use WiFi. They connect to your network using an ethernet cable. Make sure you have considered how the computer will connect to your network. If you have patchy WiFi, a wired connection is very stable but not nearly as convenient. If the desktop you have bought does not have built-in WiFi, you can add it with a USB adaptor.
Wireless Access Point: A device that plugs in to your network to extend the range or your WiFi coverage.
Mouse/Keyboard: Check whether the computer you buy comes with these. Laptops usually have built in keyboards and track pads. You can get wired or wireless keyboards and mice. I strongly recommend wired keyboards and mice for schools – no batteries to run out or mice to *ahem* run away.
Power supply: A laptop will have a specific charger with a specific voltage. Do not mix up chargers. They are often quite expensive to replace. The power supply in a desktop is built in. Unless you plan to build your own computer, you don’t need to think about this.
Motherboard: The skeleton inside the computer on which all the components sit. You probably won’t need to think about this.
Server: A computer that is always running on a network. This server provides space to save files and handle computers logging in to the network. By saving to a networked server rather than an individual machine, you can access your files on any computer that logs in to the netwrok rather than just the one you saved your files on.
UPS: Uninterruptible power supply/source. Like a big backup battery. If your desktop computer or server is plugged into a UPS, it will revert to backup battery power for a short time if the mains power goes out for any reason. It gives the computer the time to save everything and shutdown gracefully in the event of a power cut.
NAS: Network attached storage. Like a very basic server – a quick and relatively cheap way to add storage to your network.