Downgrde xp for pre installed vista hp(AMD)

Hello,
i bought last month new hp compaq (AMD)laptop there is already preinstalled windows vista, but i dont like to continued with vista then i decided to (remove or)change for os windows xp sp2 then i was searched in online, how to instlled downgrade windows ,then i got 2 methods

one for

partation method shrink volume

another one

nlite method i did above two methods sucssfully finished but finally reboot in black screen there it show me windows xp then i entered it,then it is shown me following error messages ntldr file, 0xc000000f

then right now i m using vista i dont like to continue that, i need to install xp please give me some way please help me