Reregister or rekey will be the main event as XP will see too much of a h/w change. But this process should be painless(as possible) as long as the restore CD is present since you mention Compaq. That said, if you have a orginal XP CD(not a restore one) makes this process slightly more easier.
This probably won't work but I have to ask.
My current machine is a Compaq 5102US 1 Gig processor running XP Home. I have severely customized it:
Sony 16X DVD-ROM
Sony 52-24-52 CDRW
Original 40 Gig HD
Slave 20 Gig HD
Internal Zip-100
384 Meg RAM
D-link NIC, cable modem and router
I want more speed. Can I get a new Compaq (bare bones) 2 or 3 Gig processor http://www.overstock.com/cgi-bin/d2.cgi?PAGE=PROFRAME&PROD_ID=546120 and just move everything to the new machine? My concern is Windows XP. Will it run with the new system board?

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