Over weeks and months of use, computers running any version of Windows XP and
Vista will invariably slow down significantly because of hard drive fragmentation.
First, a quick explanation about fragmentation:
When you delete a file from your hard drive, that area of your hard drive can then accept data from another file. If thefile to be saved is larger than this open area, however, Windows must split the fileinto fragments. When your computer needs to load a file, Windows automatically(and invisibly) reassembles these fragments back into the complete file. However,
the more fragmented the files are on your hard drive, the longer this step takes, and
the slower your PC becomes. When you defragment your hard drive (called a defrag), the program rearranges the data on your hard drive so that each file is contiguous (no longer divided up into individual fragments) — making it much easier and faster for Windows to read that file when you ask for it!
To defragment your hard drive, follow these simple steps:
Windows XP
1. Click the Start button, and then choose Programs➪Accessories➪
System Tools➪Disk Defragmenter.
2. From the list that appears, click the drive you want to defragment.
3. Click the Defragment button.
4. When the defragment is complete, click the Close button on the Disk
Defragmenter window to exit the program.
Windows Vista
1. Click the Start button, and then choose All Programs➪
Accessories➪System Tools➪Disk Defragmenter.
2. Click the Select Volumes button to choose which drive you want to
defragment.
3. Click the Defragment Now button and then click OK.
4. When the defragment is complete, click the Close button to exit the
program.