To insure a safe, clean and fast running pc you need to clean the PC regular. This includes hoovering inside to get rid of the dust, make sure everything is wired up to the correct periphal, and to clean and replace the thermal compound on the CPU. This is to insure that the CPU does not get to hot. The CPU is the heart of the computer which means it gets used the most in every operation which will result in a hot CPU, which means you needed to make sure the heat sink is clean of dust and has contact so it can do its job and get the heat away from the cpu as quick as possible.
