I have HP Pavilion that runs Vista and recently it has been turning off by itself. I cleaned it not too long ago but the problem started today. I don't think its a cooling problem because the back of the computer where the fan is is cool. The system just shuts off but the light stays on. I noticed that it started happening after I downloaded an update for Skype and one time when I was on the internet I saw multiple tabs open up and caught the word "Skype" before the computer shut off. Do you think uninstalling Skype would help? Also, when the computer shuts off I cant turn it back on for a few seconds (10-15 seconds). Any ideas on how to fix this?