your computer doesn't seem to launch programs or open files with the same pep as
before, hard disk fragmentation might be part of the problem.
Fragmentation is a normal result of creating and deleting files, but if it
becomes severe you'll notice your PC getting sluggish. The good news is that you
can often speed it back up by defragmenting your hard disk. Let's look at how
fragmentation occurs and what you can do about it.
What is Fragmentation?
To understand what fragmentation is, it helps to know what happens when files
are deleted and created on your hard disk.
Deleting files on your computer creates gaps of free space on your disk. When
you create a new document, image, or other file, your computer tries to write
all of the file's data into the first available area of free space.
But sometimes that space isn't big enough to hold all the data. When that
happens, your computer writes as much data as possible in that space. Then it
finds free space elsewhere on the disk and stores the rest of the file's data
Over time, your computer stores more and more files in this way, scattering
fragments of individual files across your disk. When your computer opens a
fragmented file, it has to retrieve the data from several different areas of
your disk, slowing down the process of opening files.
Defragmenting (or "defragging") rearranges the data on your hard disk
so that each file's data is stored in one location. This allows your computer to
find and load the data more quickly and efficiently.
Before You Start
There are a few things you should know about disk defragmentation before you
Defragmenting in Windows
- Although defragmenting is normally safe, there's a risk of losing data if
a power outage or some other problem interrupts the process. So back up your
important data to a removable medium, like a CD or Zip disk, before you
- Depending on how large your hard disk, defragmenting can take several
hours, and you can't use your computer while it's happening. Start it before
you leave for work or before you go to bed.
- Your disk should be error-free (see computer
maintenance tutorial for details about checking your hard disk for
Windows includes a utility called, appropriately enough, Disk Defragmenter.
Before you run it, shut down all other running programs (including background
programs like virus scanners and screensavers). Other running programs can
interfere with Disk Defragmenter, causing error messages.
If you shut down all programs and still have problems running Disk Defragmenter,
you might have to clean boot your system or restart it in Safe Mode first.
Instructions for doing so in Windows
98/Me and Windows
XP are available on Microsoft's Web site.
To start Disk Defragmenter:
At this point, if you're using Windows 2000 or XP, you can simply click the Defragment
button. If you're using Windows 98 or Me, follow these additional steps:
- Click the Start button and select Programs (Windows
98/Me/2000) or All Programs (Windows XP).
- Choose Accessories, then System Tools, and finally Disk
- Select your hard disk in the Disk Defragmenter window if it's not
in Mac OS
- Click the Settings button.
- Make sure Rearrange program files so my programs start faster is
- If you already checked your disk for errors, uncheck Check the drive
for errors to save a little time.
- Click OK to close the dialog box, and then click OK again to
The Mac OS doesn't include its own disk defragmenter; Apple's
position is that fragmentation doesn't affect a Mac's performance
"significantly." But if you want to wring every last bit of
performance out of your computer we recommend investing in a third-party
utility. Popular choices include PlusOptimizer from Alsoft,
Tech Tool Pro from Micromat,
and Norton Utilities from Symantec.
Before you buy a utility, make sure it specifically supports the version of the
Mac OS you're running. And make sure to read the documentation for the software
you choose thoroughly before you use it.
If you can't or don't want to lay down the cash for a third-party program, you
can go with Apple's suggestion: Back up the contents of your hard disk,
initialize your disk, and then restore your data. Note: Initializing
destroys all the data on the disk, so make sure you have a complete backup
before you do this!
Set a Schedule
How often should you defragment your hard disk? There aren't any hard and fast
rules, but we can offer some suggestions that work for a lot of computer users.
If you often work with very large files (like audio, video, or graphics files),
defragging once a month will help you maintain your computer's performance. If
you usually work with small files, defragging once every two months should be