Hi, sorry if this is in the wrong place but I am new as of today. This evening from 5pm my computer, whilst I have been working at it, has suddenly shown a black screen followed within seconds of all power closing down. I am speaking about a Laptop running Windows vista. This has happened 7 times in all now. It restarts ok. I did wonder at first if it was a power surge but can't see that as a possiblity. It has happened a couple of times in the past couple of months - but usually only once. I am really worried so can anyone help please. Many thanks