Technology dates frighteningly quickly, but often older machines are still perfectly usable even though you might have outgrown their capabilities. It seems a shame, therefore, to let your broken laptop languish in a cupboard or the spare room, when it could be used by someone else.

Fortunately there is a ready market for old laptops, so you can not only get rid of your old computer but make a bit of cash from it too. So, whether you’re a freelancer looking to sell a single machine or a small business looking at bulk laptop disposal, here’s what you need to know.

Identifying the machine

The first thing that you need to do is to identify what sort of machine you have. The make and model number are the first things to look at, there will usually be a spec label on the underside or the machine that gives you this information.

It’s also useful to know the size of the screen (measured diagonally); the type of processor; the amount of memory (RAM); and the capacity of the hard drive. Newer machines may have solid state drives (SSD) which are faster and more robust than physical hard disks. You also need to know which operating system the machine is running and which version.

Cleaning up your data

Inevitably when you have had a laptop for a few years it will have accumulated a lot of data, some of which could be sensitive. There are your Wi-Fi logins, passwords for your online shopping and banking, and other documents that you wouldn’t want to fall into the wrong hands, so it’s important that you delete all your data properly.

First of all backup all of your information, either to the cloud or to an external drive. You may think there’s nothing on there you want to keep, but life being what it is, you are almost certain to discover there was something you really needed a few days after everything has been wiped.

Once you have a backup, you need to remove your data. Just deleting the files, or even formatting the disk, isn’t enough as information can still be retrieved using specialist tools. Instead, you need to make certain that your files are overwritten. How you do this will depend on the type of machine you have and how old it is.

On older Windows machines – running XP, Vista or Windows 7 – you’ll need a third-party tool to wipe the data. If you search reputable freeware sites such as Snapfiles there are plenty of options available. These usually allow you to create a bootable CD that can start the machine independently of the operating system, allowing you to wipe the data on the hard drive.

From Windows 8 on, Microsoft helpfully built a disk wiping feature into the operating system. On 8 or 8.1 go to Settings and select Change PC settings, there you’ll find the option to Remove Everything and Reinstall Windows. Be sure to choose the Thoroughly option to ensure that your files are properly wiped.

Windows 10 is similar; choose Settings and then Update & Security, then select Recovery. From there you can reinstall Windows but be sure you take the Remove files and clean the drive option.

Apple systems have a similar option available. On systems before Lion or Mountain Lion, you’ll need to have your system disk. Hold down Command and R as the machine starts, this will open the recovery partition, then choose Disk Utility. On the Erase tab go for 7-pass Erase, this will overwrite the data multiple times.

Preparing for sale

Once you are sure your data has been removed, you can prepare the machine for sale. Get together any leads, manuals and discs that go with the machine. If you have the original box lurking in the loft so much the better, that will increase the value.

Make sure the machine is clean. Spending a bit of time with a damp cloth to make sure it looks its best can help to enhance its value.