Therefore, if you are long for optimizing PC performance, you should spare no efforts in removing the junk files and defragment disk.
Normally, the junk and temporary files are the priority for you to get rid of.
In the default condition, they are restored in the C system disk.
You can find them in the "c:/Documents and Settings/Username" and "c:/WINDOWS" respectively.
Since they are left by browsing on the Internet or backing up files, you feel free to get rid of them.
By doing this, you have finished part of the task of speeding up computer.
Besides removing such junks, the next step for you is to defragment disk.
In the first place, let us see why disk defragmentation can optimize computer performance.
Disk defragmenting program can unite fragment files and folders and arrange single and continuous disk space for restoring every file or folder so as to improve read-write speed.
In this way, the system can visit and restore those files and folders faster and more efficiently.
By arranging the files and folders, defragmentation can arrange available space as well and reduce the probability of creating new fragments.
You see, when the files and folders reunite again, the system may spend less time restoring or reading them.
And you can defragment disk by using the program of Windows in the "Accessories"-"System Tools" and remember that scan the whole disk before defragmentation.
While performing it, you are not allowed to use any application, because any read-write operation can hinder the speed of defragmentation, even cause it to restart again and again without completing the task.