As far as I'm aware, there is no default PM option enabled on the P33 Bios. Will unlocking the option on the BIOS via a mod enable it, or is the PM entirely hardware-reliant?
post a download link to your bios and i will see if it contains any hidden options for the port multiplier .
your bios isn`t PHOENIX , UEFI OR INSYDE .
please check your bios brand and post it in the right section as i`m only can edit PHOENIX or INSYDE .