All of the data on your computer has to be stored somewhere. These are the devices that keep your information at your fingertips.
The first hard drives for personal computers were a lot faster than floppy disks, but were big, noisy and costly devices that used incredible amounts of power.
That was Then--This is Now
While $1 per megabyte used to be considered a really good deal about ten years ago, $1 per gigabyte is now considered to be the going rate for most hard drives available today. The devices themselves have shrunk from 5.25" half-height devices in the late 1980s, to 3.5" half-height devices in the early 1990s. They assumed their 3.5" x 1" form factor in the mid-1990s, the size the vast majority of hard drives for PCs remain today. Performance has also greatly improved. Over only the last few years have hard drives gained the performance to handle video streams, which led directly to the availability of today's high-performance video editing computers. And, of course, the way hard drive capacities have grown over the last couple of decades is the most striking improvement of all.
What does this mean if you're buying a hard drive for your desktop computer today? For starters, any drive you buy will hold at least 40GB, although 80GB and 120GB drives are vastly more popular. A few very large drives (250GB and above) are also on the market, but are currently pricey.
What to Look For
Almost all desktop hard drives currently on the market are 7,200-rpm devices. A few 10,000 rpm drives are out there, and 15,000 rpm drives can be found if you know where to look. 5,400-rpm drives are becoming rare, but are usually an excellent choice if you're on a budget. The spindle speed of a drive used to be an important factor as far as performance is concerned. Now, the high aereal densities of today's drives means that the data throughput speed of a drive with a lower spindle speed can be as high as a drive with a higher spindle speed. However, a drive that operates at a higher spindle speed will still have lower latency in locating a particular file on the disk.
The majority of today's drives have 2MB buffers. However, drives with 8MB buffers are establishing a foothold in the market. The price differences between drives with 2MB and 8MB buffers are not particularly great, either. If you're looking for a video drive, though, where the majority of your files are going to be on the order of hundreds of megabytes to a few gigabytes, the benefits of an 8MB buffer are not quite as noticeable as they would be if you were dealing primarily with small files.
Almost all of the drives that you'll find at retail are standard IDE (ATA) drives. Serial ATA is starting to make inroads; promising simpler connections, smaller cables and higher speeds, but the drives still command a premium price. SCSI drives, in all of their various flavors, are generally much easier to find online than in stores. Be sure to verify which interface you need before you buy.
All of the drives sold by the usual electronic chain stores come with an installation assistance poster, a bag of screws and jumpers, and a cable, giving you all you need to install your new drive. It's generally a very straightforward process that doesn't take long to perform. It usually takes longer to format your new drive than it takes to actually install it in your computer.
Buying online, you can find some deals on what are referred to as "bare drives," which are generally purchased by system integrators or large IT departments. They're just as easy to install, but there are no poster or other hand-holding mechanisms provided. However, if you've installed a hard drive before, you probably won't have any trouble installing another drive.
RAIDs, or Redundant Arrays of Independent Disks, have experienced a recent surge in popularity as the result of motherboard chipset manufacturers (such as Intel, VIA, SiS and ALi) including RAID functionality in their recent designs. If your computer's motherboard has a built-in RAID controller, it doesn't take too much effort to build your own array right into your current computer's chassis. Configuring your array at that point involves some minor BIOS configuration adjustments and the installation of RAID management software.
If you opt to use this approach, though, be aware that your computer's power supply needs to be up to the task. While today's hard drives use a fraction of the power of the drives of the past, taxing a power supply can lead to system instability and data loss. You can get a replacement power supply for $50-100, depending on its wattage.
A number of companies sell external, pre-configured RAIDs. Some of these arrays even use USB 2.0 and FireWire connections, making them very easy to set up. Others rely on a separate controller that is included with the box of drives, which is a little more challenging to install than a plug-in-and-go USB or FireWire array. The higher throughput attained with units configured this way makes up for any installation issues you may encounter, once everything is installed correctly.
RAIDs are configured in numerous levels, which determine how they store information between the disks. Video editors generally prize Level 0 RAIDs, also known as stripe sets, which interleave the data between two drives. This makes the array operate very quickly, but a big drawback to stripe sets is that if something happens to either drive, then all of the data on the volume is rendered inaccessible. Given the high reliability of today's drives, though, this is a calculated risk that many videographers find to be worth taking.
Time to Upgrade
When it's time to increase your computer's hard drive capacity and external hard drives just don't do it for you, a new hard drive or RAID is the upgrade you want. It's quick and surprisingly easy, and the benefits of upgrading are huge.
Consult the manufacturer listing sidebars included with this article for some leads on where to start with your next storage upgrade purchase.
Charles Fulton is an Associate Editor for Videomaker.