i am a 13 year old kid interested in computer sciences,

hear is the problem: we have a computer that we think was wrecked by its external power supply, when we turn it on it sends no signal to the monitor but it beeps at regular intervals. what is the most likely failing hardware? thanks
jp

        The NOSPIN Group has added a new feature on our website,
           web based bulletinboard for questions and answers:
              Visit our sister website at http://nospin.com