Don’t forget to bakcup Vista.
Go to BIOS (press F2 on reboot) and change storage mode from AHCI to IDE.
Install XP.
Download AHCI driver (XP version) from acer.com website
Unpack AHCI driver zip file
Start cmd.exe (start > run), from AHCI unpack folder, run: “setup.exe -a -p c:” (without quotes). The files will be extracted to c:winall
Go to Control Panel > System > Hardware > Device Manager > IDE Atapi Controller, and update driver for Intel ICH9M-E/M SATA Controller using c:winall driver file.
Restart the computer.
Go to BIOS, change storage mode from IDE to AHCI.
Windows will detect new hardware.
Finish.
