Xp Pro and new System

Heres my question:- i just got a new machine (P4 1.6a) and i am currently running a p3 450 - now is it possible to switch the hadware without formating the drive- we tried on my roommates machine but we kept getting blue screen errors- if i have format i guess i can - its just a real pain in the butt- thanks for helping!

you can try it. windows will boot up and find everything thats differnt. or it just won't work. just go ahead and try it.

I dont understand what you are triing to say- can you explain further?? if you mean just putting the new hardware in that wont work - i know that for a fact