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One of tech's dirty little secrets is that no matter how much storage capacity space your PC starts off with, it'll run out of space sooner rather than later.
Storage capacity issues are becoming more severe largely thanks to the steady stream of documents, emails and multimedia disk space hogs such as MP3 music, digital photos, and video, which are gobbling up hard disk real-estate like its going out of fashion.
Worse still, living in the digital age also means that irreplaceable memories are becoming increasingly fragile. Bulky photo albums and video tapes may be going the way of the dodo, thanks to gadgets such as digital photo frames and video playback devices, but there is a downside. Hard disks are mechanical beasts, and eventually wear out, frequently consigning irreplaceable digital memories to that great recycle bin in the sky, never to be seen again.
Things needn't be that grim, however, as valuable data can be backed up, and boosting your PC's storage capacity is easier than ever. Back in the not too distant past, adding more storage to a PC definitely wasn't for the faint of heart.
Upgrades usually required that computer owners pop the lid of their desktop PC to fossick about in its guts with a screwdriver in order to add another hard disk drive. With a growing number of people now owning laptops, which lack the internal expandability of desktop PCs, popping the lid to add storage often isn't an option.
Plug 'n' Play storage specs
Sorting these storage conundrums is actually easier than you'd think, thanks to external hard drives. Essentially a hard disk in a box designed to plug into your PC, adding disk storage is about the simplest PC upgrade you're ever likely to make. There are no screwdrivers needed, few messy cables, and best of all, no delving into your computer's innards, all of which means increasing available storage can be done in a matter of minutes.
External drives range from small ultra portable pocket-sized hard drives that draw power from one or two USB (or FireWire) ports, to more bulky (but more roomy) models that are designed with limited portability in mind, typically to sitting on a desk, plugged into an external power supply.
Ultra-portable external hard drives are more portable and ideal for quickly transporting large amounts data between computers or giving your laptop a storage boost whilst on the go. Larger external hard drives are better kept in one place.
With any external hard drive, durability is an important consideration. Whilst most are housed in a protective case and are relatively dust and moisture resistant, they're not indestructible.
Hard drives are mechanical and if dropped or even moved whilst reading or writing data, they quickly become the hardware equivalent of a boat anchor. If durability is a requirement, consider purchasing a Solid State Drive (SSD). Where a mechanical hard disk consists of a rapidly spinning round platter and read/write head mounted on a record player-like stylus arm, SSD's consist of electronic memory chips which lack fragile moving parts of a mechanical hard disk, making them relatively shock proof.
There is a trade-off however, with SSD's having both their limited capacity (most SSD's max out at 160GB) and cost-per-megabyte which is calculated in dollars (mechanical hard drives is cents per MB).
Connectivity and other stuff...
Another spec to consider when shopping around for an external hard drive is the various connectivity options available. The most common form of PC connectivity is usually USB 2.0 which, in theory, can shift 480 Mbps to and from your PC, ideal for nearly any basic storage tasks you're likely to consider. USB 2.0 also trends to be the most affordable option. FireWire is another option and can transfer up to 800 Mbps, making it ideal for data intensive tasks such as video or audio editing. This said, few PCs feature a FireWire 800 capable port out of the box (Mac owners however are in luck), and FireWire external drives tend to command a price premium.
Both USB and FireWire's megabits per second (Mbps) data throughput doesn't come even remotely close to the three gigabyte-per-second (GBps) rating of the serial ATA hard drive inside your box, so if its raw speed you're after, you might want to consider an external drive with external SATA (eSATA) connectivity. This will give you close to the same 3GBps data throughput as you currently get with your PCs internal hard drive storage. eSATA interfaces on both PCs and external hard drives are still relatively uncommon and over the short term will continue to command a price premium.
As impressive as 3GBps sounds, the data throughput rates described above are always theoretical maximums and are usually going to be significantly higher than what you're likely to experience under real world conditions. This said, the faster the actual hard drive operates, the faster data can be transferred.
Ideally any hard drive you're considering should have a seek time (the time it takes to find data) of 10ms (milliseconds) or less. Most hard drives also use dedicated memory as a buffer to smooth out and boost performance. A 4MB buffer is pretty much the default minimum for most hard disks. The faster a hard disk platter spins, the better it will also perform. This is measured in RPM and higher is better. 5400rpm is the minimum, with 7200rpm being optimal.
Last but by no means least, is capacity. Choosing what storage capacity to buy is perhaps the simplest part of the whole buying equation. Simply put, buy as big a hard disk as your budget allows. Ideally you should add at least another 50 per cent to your data capacity requirements. A key measure of bang per buck to use when shopping for a hard drive is the cost per MB. This is obtained by dividing the cost of the hard disk by its capacity and will give a more accurate means of making sense of the huge variations in hard drive prices. Larger, more capacious hard drives usually tend to offer greater cost per MB bang per buck.
Seagate FreeAgent 500GB USB 2.0 Drive
A largish power adaptor and bulky form factor are clear indicators that Seagate's FreeAgent is primarily designed for use as a stationary external hard drive. This said, the FreeAgent is designed to stand vertically which turns out to be a pretty hoopy move, allowing the FreeAgent to consume less scarce desk real-estate than a paper stapler.
Cable ports are also mounted ion the FreeAgent's base, further minimalising desktop cable clutter. The FreeAgent's esspresso brown-orange design will either be seen as sophisticated or as a 70's throwback depending on personal taste. Quiet in operation, the FreeAgent also has an illuminated strip running down its front to indicate drive activity. Able to work plug-n-play fashion with Windows Vista through to Windows XP, the FreeAgent will also play nice with Apple Macs running OS X 10.3.9. This said, the FreeAgent will need to be re-formatted using the Mac's Disk Utility before it'll be usable. Available at the time of writing from Dick Smith Electronics for approx $169, the FreeAgent is a steal at a mere $0.34 per Mb.
Formac Disk Mini 320GB USB 2.0 Drive
Portability figures first and foremost with Formac's Disk Mini, which is small enough to slip into a laptop bag and can be powered using a spare USB port. Decked out in glossy piano black, the Disk Mini's case is completely sealed with only two status lights on its front giving any indication of activity (a red LED shows when it's powered up, and a green one for when data is being transferred). This is definitely a good thing, as the Disk Mini proved to be incredibly quiet when in operation. An 8MB buffer and USB 2.0 or FireWire connectivity translated into pretty solid performance, and its roomy 320 GB made it more than ideal for backing up data or transferring documents between computers whilst on the go. At the time of writing, a Disk Mini retailed for $299.19 at TotallyMac.com, which works out $0.93 per Mb, which considering this includes a faster FireWire interface plus a smaller and more costly 2.5" portable drive form factor is pretty good value for money.
Intel X25-M 80GB 2.5-inch Solid State Disk
With no mechanical parts, the use of non-volatile memory chips in Intel's X25-M Solid State Disk made it a zippy performer with a Sequential Read Transfer Rate test showing a transfer rate of 250Mb/s, whilst a write speed test delivered around 70Mb/s). Speed aside, the real reason for paying what is best described as a sizeable premium for solid state storage is durability. According the specs supplied with the drive, it has a 1000G shock rating (enough to kill most mechanical hard drives dead). Given the drive was a loan unit, I was however somewhat reluctant to pick up a baseball bat and put this to the test. Although not strictly an external drive, the X25-M's SATA connectivity means it can easily be mounted into an external drive chassis. Of the three drives tested, the X25-M had the lowest capacity at only 80GB. At the time of writing, the X25-M retailed for #1,399.99 from expansys.co.nz, which isn't terribly cheap at $17.49 per Mb. This said, durability does command a premium.
