1. Overload due to start-up programs: When you add more programs to start up, they consume more time when you start your computer. This is one of the reasons why your computer is slow. You must delete those programs from start-up that you do not require there. This will effectively speed up your computer at start and save lot of your time. Care must be taken not to remove Firewall, Anti-spyware or Anti-virus programs.

2. Temporary internet files: Temporary internet files are one of the major reasons why your computer is slow. These files occupy more space as compared to any other application as the browser caches every page that is visited for fast access later. Removing these files can go a long way in speeding up your computer. Most browsers make it easy to delete these files. Just go to your settings and options and delete. You can also configure your browser to delete them everytime your browser is closed. Regularly deleting temporary internet files and cookies can do wonders for PC speed on the internet.

3. Spyware: There is every possibility that malicious programs and spyware get embedded in your computer. This is one of the reasons why your computer is slow. As these softwares are installed without you knowing about them, you are totally unaware as to the reason for your computer being slow. The various sources that can land with spyware are music downloads, video downloads, malicious emails etc. You must scan for such malicious spyware quite often and remove them so as to speed up performance of your computer and to prevent damage to your computer. You must keep your anti-virus software updated.

4. Development of bad sectors in hard disk: You will realize why your computer is slow if you try to detect and repair disk errors. After heavy usage of hard drive, it develops bad sectors that in turn slow down the performance of hard disk. This can cause delay and stoppage of even minor applications like saving a file. Detecting and repairing disk errors can prevent this and can be done by running Error Checking utility. This can scan the hard drive and locate bad sectors. File system errors can be identified so as to ascertain whether files or folders are misplaced or not. Error checking must be done at least once a week in case you use your computer every day in order to prevent data loss.

5: Badly fragmented hard drive: Another reason why your computer is slow is disk fragmentation. It results in search by the computer of the hard disk for fragmented files so as to patch them up. This can take a considerably long time, thus slowing down your computer. Remedy for this is disk de-fragmentation which increases processing speed of hard disk. All windows has a built in defragmenter under System Tools. Just select this program and run it every so often, bi-monthly is probably the best frequency.