External Hard Drives
External Hard Drive Buying Guide
When looking to add more storage to your computer sy...
External Hard Drive Buying Guide
When looking to add more storage to your computer system you are usually left with one of two options; replace or add an additional internal hard drive or add an external hard drive. The benefits of an external hard drive is that they are much more portable, allowing you to carry large files around with you that you can share or transfer to another computer with the appropriate connections. Not only do they also provide an isolated medium to backup your files to but they are also a great storage method for users who aren't comfortable enough to open up their computer to install an internal drive. Let's look a little deeper into what external hard drive options are out there to help find the one that's best for you.
External hard drives will generally be one of two types; a 2.5” notebook drive in an enclosure or a full sized 3.5” desktop drive in an enclosure. The upside to the 2.5” drives is that they have dramatically smaller enclosure sizes and can be powered entirely from the USB port (so no extra power brick is required). These are easy hard drives to toss in your pocket and travel with – some even having built-in USB cables for even better portability. However, the nature of their small size still leaves them more expensive per gig of space to buy and they don't come in the large capacities of a 3.5” drive. With 3.5” drives, you will need an AC power adapter because the drive draws too much power to be powered just from the USB port. Not only are they available in much larger capacities but you will also find many manufacturers selling dual-drive enclosures which combine the capacities of two physical hard drives into one with the use of what is called a RAID controller. In addition to the external hard drives which connect directly to the PC itself there is also a type of enclosure called a NAS, or, Network Attached Storage device. In the next three sections I will break down all three common types of hard drive enclosures for you.
Starting at the 2.5” enclosure, this is also the smallest of the three types. As mentioned, you will pay a higher price per gigabyte of storage with a 2.5” drive but you have the added factor of convenience. Not having to carry around a bulky power adapter and sometimes not even needing to carry a USB cable (if it’s built-in to enclosure) is certainly a huge benefit for those on the go. Almost as convenient as throwing a memory stick in your briefcase, a 2.5” external drive can now offer up to half a terabyte (500 gig) in your briefcase. Since these drives are powered by the USB port the most common interface you will find for them is of course USB. However, many external 2.5” hard drives can also be found in firewire and e-SATA variants as well. These kinds of drives will either be powered through an AC adapter or a separate cable that uses a USB connection simply for power while data is transferred through either the e-SATA or firewire connection for added speed. Of course with the smaller physical size you'll see a lot of manufacturers including a carry sleeve or even a nice zipper carry pouch with their drives, just read the package to see what the included accessories are.
Shopping for a 3.5”, or full sized external hard drive will leave you with a lot more options in terms of capacity, styling and interface connections. Most of the time you'll be stuck choosing between a single or a dual-drive option. The dual-drive hard drives will usually only appear to your system as one physical drive because the enclosure will use a RAID controller to span one volume over the two drives. Doing this allows for a hard drive size larger than one physical drive can do on it's own (ie. two terabytes by using two, one terabyte hard drives). All of this happens behind the scenes though, so you don't need to worry if you don't understand what RAID is because the enclosure will take care of all that for you. With larger capacity and/or multiple drives being used, you'll see most external hard drives being cooled either with a quiet fan or just passively with no fan at all.
The interfaces used to connect the hard drive to the computer are something you will see a diverse amount of options with. Although there are only a few interfaces used, it's the combination of them that the manufacturers choose to put on that particular model of hard drive that will matter to you. Pretty much every external hard drive will have a USB port simply because that ensures maximum compatibility because practically every system has USB. The other options you may have are e-SATA, Firewire 400, Firewire 800 and some will even have a LAN connection (touched more on later).
Another feature that's more commonly present on 3.5” external hard drives verses their 2.5” counterparts is one-touch backup capability (commonly referred to as OTB). This is a button on the hard drive that will automatically trigger a file backup routine that's setup inside the included software. For example, I could set it so every time I press the button it automatically backs up my media collection from my local drive onto the external drive so I have a redundant copy in case any drive would ever fail or I accidentally delete a file. The software that comes with the enclosure to take care of this function is different with every company but they will all generally be able to handle the same type of OTB tasks and options.
NAS Hard Drives
The network attached storage hard drive is something quickly becoming more popular as more and more households have several computers and/or laptops. This is an external hard drive that connects directly into your home router, either via a network cable or wireless on some models. The hard drive then has a settings menu you can access by connecting to it through your web browser – the same way you would usually configure your internet router. From there you can usually setup a side range of different settings and options for the way the drive will operate. On your local computers you simply find the hard drive on your network and map it as a network hard drive to keep it readily available through My Computer and all of your software. Reading and writing files is performed in the same manner as doing it on a local hard drive, though keep in mind that network transfer speeds won't always make it perform as fast as a local drive!
Some NAS drives are a simple pre-built enclosure with one or more drives inside, where as other models are a separate enclosure you buy then install your own drives into it. A lot of the larger enclosures use hot-swappable drive trays to easily add as many drives as you would like as your storage needs expand.
It all probably sounds like more than it is. Once you know what your needs are for an external hard drive, that will already have answered the question of “what style do I buy?”. From there, just find the features and capacity that appeal most to you and will work with your plans for the drive.