Buying Guides

Computer desk setup

Buying a PC

Whether you’re buying your first computer, or simply replacing your old one,
this guide is here to help you pick the right model for your needs.

And if you need help getting started with your new computer - or you're having some issues with your existing one, as long as you bought it from us - our  in-store Tech Support team can help. Find out more.

Computer types

  • These are desktop computers without any additional components, such as monitors and speakers
  • They come in a variety of sizes
  • Great if you’re looking for increased power on any budget
  • Don’t forget, you’ll still need a monitor, mouse and keyboard to use it
an example of a tower computer
All-in-one desktops
  • Combines computer, monitor and speakers into one unit
  • Less cables required than a tower and monitor combination
  • Many of them also feature intuitive touch screens, perfect for creative work
  • They’re ideal for watching films and performing graphical work, thanks to their large, high quality screens
  • Apple iMacs were some of the first all-in-one desktops in the mainstream market
  • All-in-one desktops often come with a keyboard, mouse and monitor, so the cost is combined in one purchase
an example of an all in one computer
Gaming computers
  • Choose between a tower or all-in-one computer
  • Hugely powerful with dedicated graphics cards and large amounts of RAM, so you can play the latest games
an example of a gaming computer
Performance computers
  • Great if you work at home and need to have multiple advanced programmes open at the same time
  • Have a large amount of RAM and a fast processor
  • Buy a performance tower or an all-in-one
  • All-in-one computers come with a minimum 27” screen 
an example of a performance computer

Which operating system?

The operating system is the basic software that controls many of the computer's functions and also acts as an interface between the user and the microprocessor.

There’s a perennial debate over whether it’s better to purchase an Apple Mac computer or a computer running Microsoft Windows operating system.

Microsoft Windows
  • The most widely adopted system in the world
  • The newest version, Windows 10, builds on Windows 8 by integrating the start menu with the start screen
  • Windows 10 is designed to be cross-platform - one operating system, tailored for your device, whether it’s a PC, tablet or smartphone, with apps created to run across all three
  • Includes Cortana, your own personal virtual assistant who responds to your voice commands
  • There are a number of enhancements, such as the Microsoft Edge web browser
  • Windows 10 is compatible with all Windows 8 devices
  • Some new functions require specific hardware requirements, such as dual microphones for Cortana
  • Apple’s latest operating systems
  • Move seamlessly between your MacBook or iMac and your other devices
  • Make and receive iPhone calls on your Mac, even if your iPhone is in another room
  • Send and receive both iMessage and SMS text messages on your Mac
  • Start an email, document or browsing session on one device and pick it up on another
  • Mac OS High Sierra comes with new functionalities and features
  • Talk to your Mac using Siri, so you can work even faster and more efficiently
  • Ask Siri to perform tasks without having to stop what you’re doing
  • Facial recognition helps you to organise and discover your best photos
  • It uses a new file system - Apple File System (APFS) that is faster and more secure 
an image of a computer processor

Features to consider

Computer storage
  • A hard drive disc (HDD) is the computer's built-in central storage system
  • They come in different sizes, measured in gigabytes (GB) and terabytes (TB)
  • The bigger the hard drive, the more applications and files can be stored 
  • Some desktop computers come with solid state drives (SSD) or both an HDD and SSD
  • SSDs are useful for using advanced programmes as they’re faster and don't use moving parts to work (making them more reliable) - this makes them more expensive than HDDs
  • Random Access Memory (RAM) allows your computer to multitask and run smoothly
  • Measured in gigabytes - usually 8GB or 16GB per computer 
  • You will need more RAM for running advanced games and design suites 
  • Read-only Memory (ROM) is permanent memory storage for data that doesn’t change
  • Virtual memory is part of a hard disc used to store data on a temporary basis
  • It swaps it in and out of RAM as required

It’s a good idea to buy your computer with enough RAM and storage space to last you for at least five years. Bear in mind that operating system updates can take up a lot of room, as do photos and videos. How much you need depends how you use your computer - use our tables below to work out what would suit your needs.

Ram guidelines


The minimum for Windows and MacOS systems


Great for running both Windows and MacOS systems, as well as a lot of gaming


Perfect for demanding professional software and games


For gaming enthusiasts who want to run multiple apps and play all types of games, including VR


Most people will be fine with 8GB RAM.

HDD & SSD guidelines

The advantage of buying a computer with both an HDD and SSD is that you could store your operating system and apps on the SSD and the rest of your files on the HDD. This would mean that your software would run faster than it would on an HDD.

For most people who aren’t heavy gamers, 64GB - 128GB SSD combined with a 1TB HDD would be plenty of storage.




Great if you don’t need much
storage and need a cheaper option

32GB - 64GB

Basic computer tasks
will run quickly


Ideal for most people who need to
store a lot of photos and videos


A good option if you use
multiple programs simultaneously


Better if you’re storing lots of large
files such as video editing files
(Adobe Premiere or Final Cut Pro)
and Adobe Photoshop files


Best if you’re a gamer or
use a lot of media files


Best for professional users or gamers
who quickly fill up hard drives


For gaming enthusiasts

If you’re buying a computer with either an SSD or an HDD then you will need more storage overall.

As an example, 1TB could hold: 17,000 hours of music, 1000 hours of video, 310,000 images and 500 hours of movies. However, these quantities would vary from person to person because each file comes in a different size, depending on length and quality. Also, some people may store more video files than music files, for example. To make an assessment it’s best to look at your current computer storage - analyse how much storage you already use, and what type of files take up most space.


If you decide to increase the storage space or running speed on your computer at a later date, solid state drives, RAM and additional hard drive upgrades are available to buy from certain suppliers.

An alternative way to free up memory is to use online (cloud) storage such as Box, DropBox, iCloud, OneDrive, Google Drive or Amazon Drive. All of these offer between 2GB - 15GB of free storage.

Graphics (video) cards
  • Calculates the colour, position and size of all objects on the screen
  • ‘Shared’ or ‘integrated’ graphics cards use the computer’s built-in RAM for example, Intel’s HD Graphics and AMD’s Radeon HD ‘G’ series
  • They provide superb visual performance for everyday use, such as watching HD videos and viewing photos
  • Advanced or ‘dedicated’ graphics cards enable you to run complex games or design packages more smoothly
  • Dedicated graphics cards have built-in RAM to perform with increased power
  • The NVIDIA GeForce range and AMD’s Radeon HD ‘M’ series are vital for those who love advanced image and video editing, as well as games
  • 3D cards are often needed or many of today's best-selling games
Processor or Central Processing Unit (CPU)
  • Also known as the microprocessor

  • The brain of any computer, controlling all functions and actions

  • Its speed is measured in megahertz (MHz) or gigahertz (GHz), respectively millions or billions of cycles per second

  • Different processors are designed for different computing tasks

  • The most undemanding tasks (streaming, web browsing, emails, using Microsoft Office) will run smoothly on a dual-core processor

  • Processors with ‘Turbo Boost’ can deal with complex tasks for a short period of time

  • The majority of computers come with Intel processors, but there are other manufacturers


If you are looking for a new gaming computer then the graphics card,
RAM and hard drive (and/or solid state drive) should be the most influential features in your decision.

If you will be doing a lot of demanding video editing, then the processor you
choose will be just as important as the other features. Check the type of
processor your video editing software works best with.

A graphics card will also be important and again, the video editing
software you use may influence what you go for. Graphics cards
can accelerate rendering times and playback.

Disc drives

Few all-in-one computers come with a storage disc drive. However, some still do and if you’re buying a tower they’re often still feature:

Digital Video Disc (DVD) drive

  • Reads DVDs as well as audio CDs and software CD-ROMs

  • Stores up to 4.7 gigabytes of data

  • DVDs can store much more data than a CD-ROM

  • The majority of DVD drives will also write to DVD-R, DVD-RW, CD-R and CD-RW discs

DVD-RW drive

  • 'Writes to' (records onto) a blank DVD, as well as reading it

  • Useful for burning home movies to DVD

If you are buying a computer without a DVD drive, you can buy an external DVD writer to read and write your discs.


All-in-one desktops

  • Have built-in screens
  • Sizes range from 19.5” to 34”

Tower PCs

  • Require an additional monitor
  • Choose from full HD or QHD resolution

Matt or Gloss Screen?


  • Easier to view in bright light and easier to clean

  • Helps to reduce eye strain if you’re working for long periods

  • Better for colour accuracy


  • Provides vivid colours, higher contrast and deeper blacks

  • Great for gaming and watching films

  • Better for use where there is less light or glare

Internet access
  • Access broadband internet with Wi-Fi technology 
  • Towers and all-in-one desktops feature Ethernet ports
  • These give you the option to connect to your router via a cable for a faster, more secure connection
Sound cards & speakers
  • A sound card generates the computer's audio capability

  • It produces all the sounds required for audio tracks, games and so on

  • All-in-one computers have them built in

  • For the best experience, buy a set of external speakers or connect to your home speakers using bluetooth or NFC

Computers the whole family can enjoy

Software & Accessories

Most of our computers come pre-installed with a wide range of software - view individual product pages for the specifications.

There is also additional software available that doesn’t currently come pre-installed:

  • Microsoft Office
  • Security software (we stock Norton that is aimed at protecting your personal information and computer)
  • Adobe products for photo and video editing (Adobe Lightroom, Photoshop, Elements, Premiere)

If you’re looking for a tower, you may also want to invest in a separate mouse, graphic tablet or keyboard.

These come with a variety of different functions, with the latest mice for featuring touch and gesture controls to help improve your experience.

You may also want to consider an external hard drive for backing up your important data, particularly if you’re going for a cheaper model that doesn’t come with much memory.

all in one computer set up example


What are my delivery options?

FREE Standard delivery on orders over £50

We also offer next and named day delivery for an additional fee.

Click & collect is free for orders of £30 and over, or £2 if you spend less.


Installation services

We offer a comprehensive range of services to help you get your new computer up and running.

These services are currently only available through your local shop, but you can still arrange them even if you bought your computer online from us - you'll just need to produce your delivery note.

Computers Guarantee

All our computers come with at least a 2-year guarantee at no extra cost.

They also qualify for our 90 days free software support helpline.

We also offer Protect Plus that can be taken out at any time within 30 days of your original purchase - this offers extra protection against accidental damage.

Jargon buster

  • A copy of your files or software, saved on a rewriteable DVD/CD, USB flash device, external hard drive or online storage server (for example, DropBox, Box, Apple’s iCloud)

  • It’s good practice to back up your work frequently

  • Short-range wireless connection

  • Allows digital audio to be played wirelessly, for example between your computer and speakers

  • Send or stream data between connected devices instantly

  • Seamless and very high quality

Gigabyte (GB) & Terabyte (TB)
  • The standard data measurement unit

  • One gigabyte contains 1,024 megabytes

  • One terabyte contains 1,024 gigabytes

Gigahertz & megahertz
  • Used to express the speed of a computer’s central processing unit (CPU)
  • 1 gigahertz equals 1000 megahertz (MHz)

  • CPU speeds are increasing as technology improves; faster models now reach speeds of over 2GHz, with Turbo Boost speeds of 3.5GHz  

Memory card slots
  • Allows direct transfer of photos and files from your memory card to your computer
  • No need for a card reader

Voice recognition
  • Operate your computer using spoken commands

  • Use Apple’s Siri or Microsoft’s Cortana

  • No need to type, click or scroll

  • Used to connect other devices to your computer, for example, a USB port to connect to your external hard drive or a HDMI port to connect to a high definition display

  • An ethernet port allows to connect your computer to your router via a cable

  • You may need multiple ports, so think about how you will use your computer regularly

  • The next-generation USB-C™ port supports external displays, power and data transfer that's faster than regular USB 2.0

  • If you do buy a computer with USB-C™ ports, consider buying adaptors so you can use your older USB 2.0 devices

Face & fingerprint technology
  • A special reader can scan your fingerprint

  • Use the front-facing camera to identify yourself (face or iris) and unlock your computer

  • More secure than pins or passwords

Near-Field Communication (NFC)
  • Allows portable devices to establish peer-to-peer communications

  • Passes small amounts of data from one device to another by touching them or placing them a few centimetres apart

  • Quicker than Bluetooth



Our rewards credit card gives you 1.25% back in points towards vouchers when you shop with us.

John Lewis plc, 171 Victoria Street SW1E 5NN acts as a credit broker. Credit provided under exclusive arrangements with the lender John Lewis Financial Services Limited


Our rewards credit card gives you 1.25% back in points towards vouchers when you shop with us.