My 1yr warranty just ran up on my Dell and now I have a problem. My computer sounded more quiet than usual, but I did not think anything of it. I usually just always have it on with no ill effects. Well, today I turned of my computer and it went to a page that said CPU fan not detected push F1 to start. So I shut it off. The question is this a fan onthe motherboard or an auxillary fan. Is my system damaged from no fan (it seems to work). Is leaving the PC on what caused it ? How do I find out what are the bios of the system? Thanks.