XP HOME will now not boot up. The first problem i noticed was a pop up that warned me that my hard drive was nearly full depite having 8gb free. I then got the message again the next day. I did a virus scan, restore, scandisk etc, all the usual things. It now wont boot beyond the POST screen and just freezes. I tried another PSU,changed the motherboard, checked the RAM all to no avail.I tried the HD in another computer and it worked after several boots. I did a xp repair, and it worked on the other PC. When i put it back in mine it crashed again at the same point! Can anybody suggest an answer because i am stumped?