Buyer’s Guide
So you want to get an external hard drive, but have ventured online to take a look and are now dazed and confused by the choice of makes, models and sizes available? Been there! There are a number of things to consider when choosing an external hard drive, and the list below won’t be exhaustive, but does provide the key things to think about:
Desktop v. portable:
This one depends entirely on what you plan to use your external hard drive for. If you only expect to need access to your files in one location, say you’re just planning on creating a back up for your home computer or laptop, then a desktop based external hard drive would probably be right for you. These tend to be bigger models with more capacity and require an additional power pack to work. However, if you’re going to be taking your external hard drive out and about with you, you’ll probably be interested in a lightweight, more portable model. There are models on the market that only weigh a little more than your mobile phone, and we’ve looked at the some of the best ones on the Best for… portability page. For maximum portability, you really can’t go wrong with USB connected devices which derive their power from your laptop.
Disk size:
Clearly one of the most important factors is how much data you’ll be looking to store on your external hard drive. How much space you need will clearly depend on what you do with your computer and what you’re looking to use your external hard drive for – some people choose to mirror their entire hard drive, others just to store the files that are important to them, for example family photos, legal documents, etc. As a general rule, you should probably try to buy as much disk space as you possibly can afford, in order that you build in some future proofing… you never know how much capacity you’ll need in years to come!
Speed of transfer:
Speed of data transfer is driven by a number of factors, a key one being the technology employed to connect with your hard drive. Most external hard drives today use a USB 2.0 connection which has a top theoretical speed of 480MBps. Faster connections are increasingly available, including USB 3.0 which in practice is about 4 times as fast as USB 2.0, and such technologies as FireWire (with up to 800MBps) and eSATA interfaces (again theoretically delivering up to 3,000MBps). Some external drives now even come with connections that support all 3 of these technologies, meaning you can maximise your transfer rate dependent on the specifications of your computer rather than the drive itself.
Security:
One of the reasons you may be interested in an external hard drive will be to keep your files safe and secure just in case your computer decides to give up the ghost one day and take everything with it. But the downside of backing everything up to an external hard drive is that you now have all your precious files in one place, and this can be a worry for some. The answer is encryption, and many devices now come encrypted already built in to save you the hassle of doing so yourself. Encryption means that to get access to the contents of your hard drive, someone will require a password or some other form of identification (e.g. fingerprint recognition). Many manufacturers provide more secure versions of their standard models, albeit at sometimes inflated prices (think Buffalo Ministation DataVault versus the standard model).
Ease of use:
These days you’d think that you’d be able to pick up any external hard drive, simply plug it into your laptop and use it, but no. Things to watch out for include requirements to download specific types of software before you can back anything up, the need for some devices (including most eSATA devices) to have access to an external power source to run on and that many PCs don’t come with FireWire ports as standard. Standard USB 2.0/3.0 connecting devices are generally considered the easiest to use, in that they are both powered by their connection to your machine and can simply be plugged and unplugged without the need to shut down in the meantime.
Cost:
Last – but certainly not least by any stretch of the imagination – you’ll have a price in mind when shopping around for your external hard drive. It’s generally said that you should buy as much disk space as you can afford, but clearly you need to play in the other factors discussed here. Thankfully, you’ll be able to find drives that provide great value for money whatever your budget (see more on this in post on Value for Money external hard drives).
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