For the first part, I believe XP Pro supports up to two chips, but unlimited cores.
As for the second part, I need to to rephrase the question.
------------------------------Which Chip? Well, it depends on which set of thieving b@stardz you choose to support: The ones who use insider trading to enrich themselves while running their company into the ground, or the ones who illegally pay vendors to not support the first group.
Reply to Scotteq
I'm quite having a hard time figuring out what you want to know on your question. Why do you need to ask how many processors windows xp can support? I guess XP can still support the latest processor from intel so all your base are covered.
This is a trick question that has no valid answers on it... 32 operating systems?? Where did you get those figures man? Are you serious?