I think I have found the answer myself, see:-
https://wiki.ubuntu.com/Core_2_Duo_Support
So - does any Linux distribution install "out of the box" on an Intel 965 chip based system yet?
But that article suggests that the problem is using a PATA CD Rom on a chipset that is only directly aware of SATA drives.
In fact one of the workarounds suggested is to use a PATA-SATA converter to get in to exactly the same position you are in now (all SATA drives)
This is a sort of related problem, but it's not the problem you are having.
What is relevant is the stuff at the end of that page..where the guy is talking about different ports connecting to different controllers.