Hallo,
I was able to install XP on a Sony Vaio laptop following the instructions of @Fernando . I had to add the right AHCI driver and push F5 during install. Selected Standard PC, else i had an installation error.
After many tries of different settings in the bios and the installation (MPU ACPI, ACPI-PC,…) i came to the conclusion, that the bios i have isn’t made for win xp. I guess some table entries are missing.
Is it possible to mod the existing bios and make it ACPI compatible for Win XP?
I doubt, that this will be possible at all, but the chances to brick the laptop or to make it unusable for modern Windows Operating Systems are very high.
Be happy, that you finally managed it to get XP installed.
I just wanted to leave here, A linux Distro might also work. Linux Mint has a nice lightwight (Xfce) version perfect for older hardware!
https://linuxmint.com/download.php