[CentOS] Centos 4.4 install on ASUS A8V-VM does not find SATA drives

Yes, I know someone last week asked a similar question (Problem with ASUS
P5VD2-X X SATA II) but the only answer I saw on that thread was the
equivalent of "I've heard it's bad so I won't do it."  Unfortunately, that
doesn't help me much.

The BIOS does indeed recognise my two SATA hard drives, and I've got the
BIOS set to "IDE" (which disables "hardware" RAID but not the SATA but
itself).  The install routine for Centos, however, does not seem to
recognise that the drives are there (or even that the VIA bridge exists via
auto search); if I try to manually select it I'm told it found a VIA
VT86c100A Rhine-II PCI (via-rhine).  Setting to AHCI does not seem to have
an effect.  I was hoping to use software RAID, and so didn't want to enable
RAID on the motherboard.

Does anyone have any suggestions as to how to either nudge the installation,
or configure the hardware, to find the SATA drives so I can configure RAID?
This is a NEW install on new drives, so it's not as if I've got an existing
configuration I'm trying to augment.

Thanks in advance,
 -Don