uncheck them in start up programs? Those will help to make you computer start faster. Other things, you may want to try ccleaner to delete all the unnecessary temp/backup files. Also defragment your harddisk afterward.
How big is the RAM you have in your machine? Upgrading it would make a big difference also.
I am just wondering that whether one can enhance the speed and performance of a PC just by disabling all the unused devices in a system?

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