It happened recently. The model is HP Presario 2500 and I bought it about 1.5 ago. It worked pretty good for the whole period, but now I noteced that one of the fans starts more often than it was before. Please, advise me what I need to do. I do defragmentation regularly, have dowloaded all recommended antyspyware, have sophos installed, the 40 GB HDD still has 15 gb free. What happened with fan, old? Thanks in advance.