I have yet to get XP RC1 to ask me to reactivate, or any other inconvience. I have swapped video and sound, added and removed a scsi controller. My only hangup was the silly par port camera, which works, but is not setup correctly according to XP's device manager. Now Im curious...I have the time to deal with Microsoft to get the activation sorted out if I mess it up....but I cant seem to get it upset enough despite multiple hardware changes. I have almost identical machines side by side running XP and 2000, and XP is by far the least troublesome.....I must have the luck of the irish or something....XP is kicking 2000 Pro's tail in ease of use around here.