Hi , andy you dont say wether or not you have a laptop or a tower system if tower system , remove cover then look for small square fan ontop of silver heat sink, if covered in dust clean off all dust also check to see if fan is working if not replace fan as C.P.U. will overheat and switch off computer , fan must work all the time other wise computer will switch off all the time hope this helps
jim, January 2010
