install question (P3 and P4)

[Simon Buchanan <nmc@orcon.net.nz>]

hi there...im about to install debian testing onto a box here. Its faily 
urgent that i get this up and running (like today), but my new P4 
motherboard wont turn up until tomorrow... I have a P3 type 
motherboard... my question is:

If i install into my system, with the P3 and P3 motherboard, what will 
happen if i put my P4 and P4 motherboard in later?

The system uses all the same CD/LAN/HD etc.