My computer always turns off, HELP PLS

Gud pm, I'm new here but I'm really desperate to fix my computer that's why I'm asking for help :D. This what happens, FIRST it restarts over and over again, whenever the windows xp logo appears and under it shows that it was loading, before it finish loading, it restarts automatically. My brother told me that maybe my windows got corrupt so I have to reformat it and that's what I did. I sacrifice all my files, music, movies to fix it :( . Now, I'm reformatting my computer but here comes the problem, it always turns off automatically when it reaches 60% or something. That's why I never able to finish installing the windows. I already tried it 3 times but it always happen. I Hope someone can help me, what can I do? is there any alternative? Thanks much in advance