Hi all, on a pc of a friend, all of a sudden while using it, win xp freezes, there is nothing we can do but turning it off. The mouse icon freezes and the keyboard does not respond; CTRL+ALT+DEL produces no effects. It happens 4-5 times during a day, while doing different things: working with office applications, browsing the internet, reading emails. Antivirus (norton) is OK. The bad thing is that there is no error message on the even viewer... What could I check? Thanks, D.