How to buy upgrades that are compatible with your computer

The process of fitting upgrades is usually surprisingly easy. They simply slot or clip into place. In fact, the tricky part of the whole business is ensuring you buy the right part in the first place.

Just as you couldn’t expect to buy an engine for one model of car and fit it easily into another, the same logic applies to PCs. Computer components come in all shapes and sizes and it’s vital to get the ones that match your PC – taking a guess is likely to end in frustration.

But how do you find out which type you need in the first place? Often this can come down to identifying the type of sockets inside, and that can be a little fiddly.

Don’t panic, though. In this section we’ll look at each common upgrade in turn, explaining the key decisions that you’ll need to make and what to look for.

Hard disks and optical drives
If you’re fitting a hard disk into any laptop made in the past five years then you will need a 2.5in Sata model. A Sata cable is pictured below.

The larger 3.5in models cannot fit inside a laptop case, and the older IDE connection (pictured below) is almost unheard of in laptops today.

Changing a laptop’s internal optical drive is not something we recommend taking on. If you want to add a Blu-ray drive, get one that connects to a standard USB2 port.

If you are upgrading a desktop computer’s storage devices, though, it is important to ensure you get the right connector. Both hard disks and optical discs used to be available in two types: some used the newer Sata connector, while others used an older type known as IDE or ATA, and sometimes referred to now as Pata.

The two are easy to tell apart, though. Look at the back of the existing hard disk. If two thin cables are connected, with one of the two plugs less than 15mm wide and the other not much bigger, it is a Sata disk. If one of the connectors is a plug around 55mm wide, that’s an IDE connector.

If you find a Sata connection, trace the cable back to the motherboard: normally you will see that there is at least one spare port next to the one where it is connected.

If you are buying a new hard disk for a desktop PC, look for a 3.5in model – these are the standard size, and are cheaper than laptop disks. For optical drives, you want a standard 5.25in drive. If you are buying an SSD it will be a 2.5in model, so you should also buy a 2.5in to 3.5in mounting bracket, which cost a few pounds.