Dual boot problems with pre-installed Windows 7

[Professor Paradox]

About two days ago I tried to dual boot my pre-installed Windows 7 machine with Windows XP pro. I created a 40gb NTFS partition, restarted my PC, went to the bios and switched from AHCI to IDE mode. I inserted the XP pro CD and installed as usual. My problems began when I booted into XP. I had no internet, no sound, no sound driver, and my display driver was replaced with a standard generic one. My network adapter/ethernet drivers were missing as well. I tried booting back into windows 7 by going to in the bios and switching from IDE to AHCI, and rebooted. Instead of booting to windows 7 it attempted to boot into XP only to give me a BSOD. Seeing as I couldn't boot in windows 7 I inserted the system recovery CDs, and reformatted my hard drive and re-installed windows 7.

My question is what did I do wrong? I'm thinking this is because I didn't install any AHCI/RAID drivers.

 

[Emerald]

http://www.howtogeek.com/howto/8790/dual-boot-your-pre-installed-windows-7-computer-with-xp/