Updated: 03 Aug 2010

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Introduction

Backup your files, photos and memories with one of our 7 tested desktop external hard drives.

Hard-drive failure is the most common computer fault. If you haven’t backed up your computer, you could lose everything. Using an external hard drive could save you money, time and heartache.

We tested 7 massive 2TB (2000GB) desktop hard drives.

Models we tested

This report contains test results and recommendations for the following external hard drives:

Checklist

Why choose an external hard drive?

External hard drives are portable and can be used on any computer as long as they have a USB, FireWire or eSATA connection (see 'Connection type', below). Installation is simple – just plug it into the computer. They can also perform regular backups so that when your computer dies (and eventually all computers do) you won't have to deal with the pain of losing years of data.

Tip: When you’re not using it, keep your external drive separate from your computer. We've heard of thieves breaking into homes and stealing computers plus the attached external hard drive (with all its backups). However, when you move the external drive be careful: a hard knock or a fall can damage it and you may lose your valuable backup data.

What's available?

There are 3 main types of external hard drive - portable, desktop and NAS.

Portable drives
These use similar hard drives to those in laptop computers, generally 2.5 inch. They're light, small enough to be transported and range from around 160 to 500GB of storage space. They're typically powered through the USB port, and some have a USB power-sharing cable or USB/power combo cable, which means there's less to carry when you transport the drive.

Portable drives are usually made with a rugged, shock-resistant enclosure since they're more likely to take knocks than desktop drives.

Desktop drives
Most home users opt for a desktop drive as they're simple to set up, easy to use and don't require any networking knowledge. They use 3.5 inch drives (the same type generally used in desktop computers). They weigh a kilogram or more, so are not as easily transported as portable drives. But they're considerably cheaper per megabyte than portable drives and tend to have a larger capacity - up to several terabytes.

Unlike NAS drives (see below), desktop drives can only be accessed by one user at a time. They're powered by an AC adapter. Our test is of desktop drives.

NAS
A Network Attached Storage (NAS) drive is mostly used for file sharing and additional storage space. They can be connected to a router via an ethernet connection and allow multiple computers on a single network to share storage. They're often used in small businesses, but multiple users on a home network use them for a central storage unit or for backing up all the computers.

If you're looking for a hard drive to be portable, compact and used in various locations, opt for a portable or desktop based hard drive. But if you want a network hard drive to be kept in a single location, and desktop real estate isn't a factor, a NAS based drive would be a better option. NAS drives typically weigh 1-5kg, whereas desktop drives only weigh 1-2kg. Don't forget the look and style factors as well.
 

Specifications and features

Capacity

How much hard drive space do you need? The table below shows how much you can store on a hard drive.

Hard drive size	Photos	MP3 songs	DVD video
100GB	28,000	25,000	45 hours
250GB	70,000	60,000	110 hours
500GB	140,000	125,000	220 hours
1TB	280,000	250,000	440 hours

Storing 280,000 photos or 250,000 songs may seem unlikely, but the figures illustrate the vast amount of data that can be stored. The larger drives are suitable for people doing lots of photo- or video-editing - if you're using high definition video a 1TB drive will only store about 120 hours of content.

Get more space than you think you'll need, especially if you're planning on using the same computer for several years.

Revolutions per minutes (RPM)

The higher the RPM, the faster the drive can read or write data. A common RPM for hard drives is 7200, with high-end drives having speeds of 10,000 RPM. Be wary of models that don't have a stated rotational speed.

Buffer

A drive's buffer is an amount of RAM on the drive to store frequently accessed data. The more buffer RAM on the drive, the more data can be stored in the cache to decrease the amount of physical drive operation. Most drives today come with an 8MB drive buffer. Some high-end drives come with a larger 16MB buffer.

Connection type

• USB 2.0 is the most common connection for hard drives and generally gives the slowest speeds.
• FireWire (in speeds of 400 and 800) is not as common but is generally faster than USB 2.0 - and with some drives it can be more than twice as fast.
• eSATA is faster than FireWire 400 and often faster than FireWire 800, depending on the drive.
• USB 3.0 is new and not widely available, but will become the USB standard. It’s similar in speed to eSATA and FireWire 800.
   
• Ethernet is used for NAS-based drives to connect across a network.

Tip: Make sure the connections on the drive match the connections on your computer.

Media/card readers

These devices are typically used to read the data from a memory card such as Compact Flash (CF), Secure Digital (SD) or MultiMedia Card (MMC). Some drives feature these devices as standard.

Seek time

Seek time (the length of time taken to find a particular piece of data) is often considered a big deal in terms of specs, but it really makes little difference. It's measured in milliseconds with the lower the figure the better the seek time. Most home or small business users wouldn't notice the difference between seek times.