Netbsd 4.0 hangs on AMD64 athlon dual core on nvidia board

[vincentd <vincent.delft%gmail.com@localhost>]

I've got some issues with my new hardware ;(.
"
cpu: AMD ATHLON 64 X2 4800+ SOCKET AM2
motherboard: MSI K9N NEO F V2
RAM:2 GB DDRII 667 MHZ
Storage:        320 GB SATA II
CDROM:  DVD +/- RW 2 layers SATA
GRAPHIC: NVIDIA GEFORCE 8600 GT 512 MB
"

I'm on Linux since many years, but netbsd is new to me. Thus some help
is welcome.

General info:
- I'm using Grub (from my linux system) to start the netbsd. The
config is:
"
root(hd0,0,a)
chainloader +1
"
- I've dediceted a primary partition for netbsd (Linux reside on same
disk but on a logical partition)


I've made several trials, here after some details:
- I've burn a CD with the AMD64cd.iso. But when I boot on it, it
hangs.
I've tried "boot -v" and "boot -x", but I've not much info on the root
cause of the problem
How could I got more detailed about this ?

- I'm able to boot the install cd if I'm desabling ACPI.
In this case, the installation cannot be performed via the CD: "device
not configured".
I've done the installation via FTP; and my first netbsd sounds to be
working fine when I'm desabling acpi.
How to desable it for every boot ? is there a config file where I can
put force such parameter ?

But cdrom is not yet recognize ;(
On my linux system, the cdrom is saw like this:
"
ata5.00: ATAPI: TSSTcorp CDDVDW SH-S223F, SB00, max UDMA/100, ATAPI
AN
ata5.00: configured for UDMA/100
"
How to enable my cdrom on netbsd ?



Should I back to a 32bit version ?
Should I back to netbsd 3.1 ?


Many thanks for your help.