AB9 Pro Motherboard SATA/AHCI installation problem

[Alan Cox]

> thought this might be because the SATA interface needed to be switched
> to AHCI mode but on doing this the disks are no longer visible at all at
> boot time so the system refuses to even start booting.

AHCI is the best mode but you then need the AHCI drivers to be in the
initrd for booting.
> 
> So I have set the SATA disks back to IDE mode, and noticed that my old
> Slackware installation still boots (using the grub loader installed by
> Fedora!).  Why does my Slackware still boot when Fedora can't seem to
> see the disks at all?

What does slackware report the disk controller in question as ?