3 days ago, my macbook air suddenly became slow and whenever i want to surf net or open anything, it will stop a while and show spinning wheel.Before that its perform as normal. I decided to reinstall mac os x leopard and its still the same. I have checked using techtool and aparently my hardisk is healthy and passed the test. Now my macbook air is consider fresh after reinstalling it but still same prob. Can anyone enlighten me?