The frequency of maintenance depends on your specific system and usage, but in general you should plan to perform a thorough maintenance check at least once every 6-12 months. During this process, you should check all of your internal components such as your fan, RAM sticks and CPU, as well as making sure your anti-virus and security software is up to date. Additionally, you should use disk cleanup and other maintenance tools to periodically scrub the excess files and clutter from your hard drive.