Hello, my friend's computer locks up when it tries to load Windows XP. He had just reformatted the harddrive. It locks up right on the Windows Loading Screen. He's tried other harddrives and had the same problem. I tried suggesting a couple of things but he didn't want to listen to me. I'm thinking more along the ram or processor, I'm not sure. All I know about the computer is its a Compaq, AMD Sempron. I can find out more specifications later on but what do you guys think would be causing this. Thanks Much.