How it could enhance the processing capability of typical destop computer?

Answer 1

There are several ways. One of them is to use software such as tweak, all kinds of optimization software (for instance jv16) which are able to clean the registry and do defragmentation of it. Also you need to defragment all your hard drives periodically (once per month or more often depending on how often you modify/copy/delete data).

You can use also hardware tricks like overclocking. Also to make an upgrade might a good idea if your computer is rather old or lacking power. You might need to add some RAM, replace the system hard drive with a drive with better performance. You might consider upgrading the CPU (if the motherboard supports newer CPUs). Also the video card might cause some discomfort especially if you are working under Vista.