Move XP to another system; go back to 98

I am building a new computer and do not wish to purchase XP Pro again. I want to remove XP from current system and move it to the new one, and revert back to Win 98 for the current system. As I understand it, Microsoft keeps track of my components as registered and will not allow me to use XP on two computers unless I purchase a 2nd copy. Would it make more sense to purchase an OEM version of XP? In any case, my Pro version needs to be on the new system, so is there a procedure to move XP over to new hardware? Thank you.

 

If its a full retail version of XP Pro (and not pre-installed or OEM) you can do what you want, provided you fully remove it from the other system.

If its not been activated or re-activated in the last 3 months or so, it should activate OK on the new PC. If not, a phone call to MS should fix it.

 

Thanks, kiwi. Is there something about file formats used by XP that would cause a problem if I remove XP and install Win98 on the old system? I don't want to lose my data files.