I wonder whether you may be able to help me with a problem my 20 inch intel core duo mac is having. Basically i need to know whether its a hard drive issue for not. My mac started to switch itself off completely with no warning. Recently it will literally come on for a few minutes and go off again. I then have to wait some time (and i usually n plug it and re plug it in) before it works again. I wonder whether something has been dislodged perhaps. Im poised to go and buy a new hard drive but if you think its something more serious then i wont bother.