K8N-E Deluxe: No DMA on IDE Disks

[Jim Wiggs <jim.wiggs@gmail.com>]

 Folks,

  I've got a box built on the ASUS K8N-E Deluxe motherboard, and I absolutely
can not get DMA working on my hard drives.  I am running the Debian 2.6.11
kernel, to which I have applied the fixes suggested at:

  http://download.nvidia.com/XFree86/nforce/1.0-0301/KnownProblems.html

  But no joy.  My only clue is that there are dmesg log messages which seem
to suggest that by the time the NFORCE driver loads, the generic IDE drivers
have already grabbed control of the ide interfaces (NFORCE3-250: "port 0x01f0
already claimed by ide0").  But how do I prevent this from happening?  I've
tried going into /etc/modules and replacing ide-generic with amd74xx, and
also replacing ide-generic with amd74xx in /etc/modprobe.d/aliases for
block devices 3 (hda) and 22 (hdc) but all that happens then is that I have
no IDE drive capability at all.  What do I need to do?  I've been Googling the
web, groups, and nVidia website off and on for weeks with absolutely no
luck on this problem.  Any help would be greatly appreciated...

regards,
Jim Wiggs