Eric, I believe that you are correct in your assumption of new hardware and
the OEM Software that (HP / Compaq) has used to package these machines. Error
has shown on system with identical motherboard replacement from HP and system
will not boot to safe mode - error reports: windows xp is has not completed
install and to run setup. Was able to force full system restore (advanced
mode) using there F10 key on boot without the system restore disk. This was
done because HP has some propritary hardware ID in there OEM package (restore
disk report that system the original system). You may have just 2 option with
this issue, purchase the full version and install your OS. The other would be
to send system back to HP (as they would request - Of Course) and deal with
the not so corropertive proprietary corporation that forces you to buy there
hardware at top dollar. Granted they can build some nice machine but when it
comes down to there customer in situation like this, they leave you high and
dry.