PATA disks/DVD not detected on ATI IXP 700 - cannot boot

[Ted Faber]

Hi.

I'm trying to upgrade a machine to a new motherboard (the ECS
A790GXM-AD3 AM3 790GX) my FreeBSD 7-STABLE system (GENERIC kernel,
compiled from source on 10 Sept 2009) reaches the point where it's going
to mount the root file system and can't find the disk.  It drops me into
the manual specification of root file system menu, but there are no
GEOM-managed disks to choose from.  

There's only one drive in the system, a PATA-connected drive that boots
correctly under the old (and I do mean old, circa 2005) motherboard.
Booting from an install/rescue CDROM on a PATA_connected drive proceeds
about the same: boots but cannot find the CDROM to mount.  SATA drives
seem to be found correctly, but I don't have any with FreeBSD on them. 

The ATA controller reports itself as an ATI IXP 700.

There's more info on the motherboard here:
http://www.newegg.com/Product/Product.aspx?Item=N82E16813135236&nm_mc=TEMC-RMA-Approvel&cm_mmc=TEMC-RMA-Approvel-_-Content-_-text-_-

I haven't tried to boot from a USB drive yet, because ATA has so rarely
failed me in the past, but I'm happy to do whatever will help to provide
more diagnostic info.  (The machine is at home, so I won't be able to do
much data-gathering until tonight.)

Thanks for any help.

-- 
Ted Faber
http://www.isi.edu/~faber           PGP: http://www.isi.edu/~faber/pubkeys.asc
Unexpected attachment on this mail? See http://www.isi.edu/~faber/FAQ.html#SIG
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