So I have a Windows 7 Hp Laptop, and when I press the power button, it "turns on", and by that, I mean the fan starts spinning and the volume control lights come on. But it shuts down after a few seconds. It does not show the Bios, and I took it apart and cleaned it so it is not a heat problem(and I did put it back correctly so it wasn't me taking it apart and breaking it). What should I do, not only was it a good laptop, I want to know what the problem was so as to avoid it with my future computers. Thanks in advance.