i have had a copy of windows xp home installed on a computer i built(padme) and in the past month i have changed every peice of hardware in it. i had another computer laying around, so, i installed my copy of windows xo home again. i thought i would run into a problem, but the activation went through right away. i was gona buy a new copy of xp for my other machine(padme), but, do i need to? i had to call up microsoft before when i just changed a stick of ram and a video card, but, i installed the same copy of xp on a completely diffrent pc, whats up with that?