So, my mother bought a MomentusXT to replace her broken HD. I hooked it up, and installed windows vista. While installing i noticed it only had 80 GB's of space, i disregarded that as some fluke. When windows was finished installing i decided to check the space left just to be sure, and it was, again, 80GB (Less now since windows was on it, but that doesn't matter). The box, and the website both say 500GB. What could be wrong?