Your hard drive is arguably the most important component of your laptop or desktop computer. Without it ... well, all you have is memory, a power supply, a CPU, and a few other odds and ends. If a computer's CPU is the brains, then the hard drive is the heart and lungs of your PC.
Sometimes, though, you might find that you need a new hard drive. But buying one isn't always easy. There is a tangle of terminology to deal with, and there are a number of factors that you have to consider before putting your money down. Regardless of why you need a hard drive, this TechTip will arm you with the knowledge that you need to choose the one that's right for you.
Why buy a new hard drive?
Hard drives can be funny things. They tend to fill up with files faster than you expect them to. All those MP3 files, movies, graphics, and documents (not to mention all of the software you install) can eat up a lot of hard drive space. A bigger drive is definitely a boon.
If you're doing work with graphics, audio, or video, your computer will be reading from and writing to the disk a lot. Even if you have a lot of RAM and a fast processor, many operations will be slow. That's when you may need to think about a faster hard drive.
The lifespan of a hard drive is limited -- anywhere from three to five years. Maybe a little more. No matter how well you care for your computer's drive and what you do -- defrag it, reformat the drive, and the like -- it will eventually up and die.
If your hard drive shows any of those symptoms, then it's time to get a new one.
Types of hard drives
Not all hard drives are the same. The two most common types of drives are IDE and and SATA.
IDE is short for Integrated Drive Electronics -- these types of drives are sometimes known as ATA or PATA. IDE has been the standard type of drive in personal computers for well over a decade now. When IDE drives were introduced, the innovation that it brought to the table was that the electronics for controlling the drive were moved from the PC motherboard to the drive itself. This ensured that the drives were compatible with as wide a range of other hardware as possible.
One of the distinguishing features of an IDE hard drive is the cable used to connect it to the motherboard. The cable looks like a big, gray ribbon. The connectors themselves had either 40 or 80 wires attached from the main body of the ribbon. Each ribbon connects to a pin on the hard drive, and either carries data or is used for grounding.
SATA, short for Serial Advanced Technology Attachment, was introduced in 2003 and is gradually becoming the standard for PC hard drives. SATA offers faster data transfer rates than IDE, and the connectors are smaller. On top of that, you can hot swap drives while your computer is working.
The SATA cables themselves look sort of like network cables. The connectors have seven pins. What's interesting about SATA cables is that they enable you to use notebook hard drives in desktop computers, something that can't be done with IDE hard drives.
Newer motherboards have connectors for both IDE and SATA drives. If yours only has one set of connectors, then you're stuck using an IDE hard drive.
Note: This TechTip offers a good look at the differences between IDE and SATA drives.
The need for speed
This is an easy one. Most modern desktop hard drives have a speed of 7200 rpm. They spin 7,200 times per minute and can read about 1 Gbit of information per second from the surface of the disk. Notebook hard drives usually have a speed of 5400 rpm; they spin 5,400 time per minute.
You can still get desktop hard drives with a speed of 5400 rpm, but these are becoming rare. As are notebook hard drives that spin at 4200 rpm; 7200 rpm notebook drives are available, but they cost a bit more.
I can still remember when around 120 MB was considered enough hard drive space. In fact, when I got a 540 MB hard drive, I had about as much space as I needed. Those days are, obviously, long gone. That 540 MB drive couldn't hold a modern operating system, let alone a fraction of my photos and MP3s. In fact, I have a couple of USB flash drives that hold almost eight times as much as that old drive.
Nowadays, most new computers come with at least a 120 GB hard drive. For less than a hundred dollars (depending on who you're buying from), you can often get a bigger hard drive installed.
But if you're buying a replacement drive, then you have quite a few options. The standard hard drive sizes nowadays are 120 GB, 160 GB, 250 GB, 320 GB, 400 GB, and 500 GB. You can also buy 750 GB drives and, depending on the vendor, a 1 TB drive. TB is short for terabyte, and is equal to 1,000 GB. That's a lot of hard drive space!
How much drive you need depends on what you use your computer for. If you just use your PC to access the Web, do household accounts, and just general computing, then a 120 GB to 160 GB should be plenty. If you're doing audio editing and graphics, or have a large collection of music and photos, then a drive in the 320 GB range should be enough. Anything else, like making music or working with video then you'll probably need at least 500 GB; music and video files can get pretty large.
Going external instead
If you have a lot of files that you don't use regularly, then you might be tempted to buy an external hard drive. There's nothing wrong with that. An external drive is a great way to back up your files (which is something that you should be doing regularly anyway). You can find out more about external drives in this TechTip.
But remember the average lifespan of a hard drive? If yours is coming to the end of its life and if getting noticeably slower, then you're going to have to replace it regardless of whether or not you have a big external drive.
Choosing your drive
Now that you know the language and what to look for, you're ready to buy a drive. Here are a few pieces of advice:
Go for a fairly large hard drive; 200 GB or 320 GB at least. Even if you can't see yourself using a fraction of the space on the drive immediately, remember that you're also trying to future proof yourself. You definitely don't know how much hard drive space you'll be using in a year or two.
Another good guide is to get a drive that's one and a half to two times the size of your current one, if possible. Of course, if you have a 500 GB or 750 GB drive that might not be possible. But you can try putting another drive in your computer -- assuming that it has enough space and connectors. Use the new drive for storage and the old one for applications.
Speed is important if you need fast access to the disk -- for example, when working with video or when gaming. In those cases, definitely switch to a faster hard drive. Or, if your computer supports it, get a SATA drive.
No matter what people might say, the brand of hard drive can be important. Some are definitely better than others. My more technically-inclined friends often recommend drives from Seagate, Western Digital, and Samsung. I know one or two people who also recommend Hitachi hard drives.
While choosing a new hard drive seems like a difficult task, it really isn't. If you're armed with enough knowledge and know what you want and need, then the job is definitely a lot easier.