A similar thread was posted by BoilingFrogs in thread 742573.
Just thought I would update on my earlier response in that thread.
I had a customer who brought in a Fujitsu Siemens Scaleo P machine preconfigured with Vista.
They decided after trying it that they would like XP installed in place of Vista.
Just trying to install XP would result in the message 'No Hard disk available' during the install.
The BIOS is not the same as BoilingFrogs quoted and I tried several options to no avail. In the end I set the BIOS to manufacturers default settings and the installation proceeded without problem (except of course finding the XP drivers for the hardware).
I know this seems all about MS but as BoilingFrogs said it also prevented Linux install on his machine