The files on your PC will become fragmented every time you use your computer. It means that these files are split into millions of pieces and it occurs even more when they are modified. So whenever you access the file or even read the file, it takes much longer time than necessary. This is because Windows has to first collect each peace of the file before you can access it. It makes your PC slower than usual. It also leads to slower boot. 
Defragging your computer puts the pieces of your files back together into a single piece. A defragmented computer will boot quicker, files will be accessed faster, and your applications will not hang. A good disk defragger will not only defragment, but will also consolidate the free space on your drives into one large piece so when you create a new file, there will be enough free space to save that file in a single piece, rather than fragmenting right away. Defrag for a faster computer and a healthy PC.
Raxco PerfectDisk 2008 Professional is best solution for all these problems. It has ability to automatically perform defragmentation when your system is idle.
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