Arno wrote:

It should not make a difference.

I'm thinking that an XP system that was installed with SATA drivers,
with the controller in SATA -mode, will not be able to boot if the
controller is put into IDE-compatibility mode in the bios setup. Reason
being that the system drivers would have incorporated the SATA drivers
(not the IDE drivers) to perform 32-bit drive access, and upon loading
them the system would find no drives attached to the SATA controller or
might not even find the sata controller - because the controller is now
emulating an IDE interface.