Hi Last night I left my PC for about an hour and when I came back the fan had switched off and the pc appeared to have shut down (monitor was saying no live PC connection) but the power light was still on at the front. It switched the PC off at the main electric supply but now it won't switch on again. When the power switch is pressed the light doesn't come on. It is receiving power though as a small fan starts but the main big fan does one rotation and then stops. Any ideas? I wondered if the fan was broken and the PC was recognising this and preventing it starting. It's 3 month's old. Can anyone offer any advice?