I currently have PC that I am trying to re-install Windows XP Pro on it. The PC shuts down during different points of the installation. Sometimes when there is 20 minutes left and other times when there is 34 minutes left to install. Needless to say this is frustrating as I can't even get Windows back. When the PC shuts down, the monitor signal is lost, the CPU fan stops but the hard drive light is on non-stop. THe only way to shut it down is to unplug and re-plug. Any ideas what the issue could be?