Okay when I power on my pc with Windows Vista it will go as far as the screen that I have my password protection on and then it will go to this bright blue screen that has a message at the end that says crash dumping to memory. it doesn't stay on long enough for me to read the screen in its entirety before it completely shuts off. As of now my computer has been on for over 30mins without shutting down but it usually shuts down when I'm in the middle of something or at start up.