how to downgrade factory installed os windows 8.1 to windows xp

If you have an HP Pavilion or Compaq Presario consumer notebook computer that shipped with Windows 7 or Vista, changing the operating system (OS) might cause severe operational problems. Many of the components, such as sound, video, graphics, network connectivity, drives, or other devices and peripherals, might have limited functionality, or might not work at all.

also XP compatible drivers may not be available for your laptop.

yet you can go through this video

https://www.youtube.com/watch?v=7O7ltJDjRYw