As promised, there is the final configuration for my PowerEdge 350.

I will be glad to know about possible mistakes in the configuration.
But it seems working fine now.

1.  The GENERIC.local file:

The console is being redirected to the second serial port (in the front
side of the server).  It is a useful feature for a 1U rack server!

It seems that only ACPI buttons are supported by this server.  I enabled
all ACPI devices and only this one appeared in the output of dmesg.  That
is the reason most devices are disabled in this file.  Enabling ACPI
buttons allows us to cleanly turn off the server using the power button
on the front side.  The sleep button should work too, but I have not
tried it.  Ok, I know that, as a server, this machine should not be turned
off usually, but having a chance to cleanly turn it off without privileged
access to the server is sometimes useful.

Temperature should be easy to monitor from the Inter IC (I2C) bus,
but I had no luck.  In fact, the I2C framework was written for NetBSD
but the iic(4) man page is not available in this operating system,
nor the iic* entry in the GENERIC configuration file.  Information
about fans, voltage and temperature should be available from the
National Semiconductor LM81 sensor.  Hope support for this sensor
will be available soon!

Currently there is some I2C support in /usr/src/sys/dev/i2c, but
it seems not enabled by default...

I will try enabling lm0, but it seems limited to LM7[89].

---------------------------------------------------------
#	$NetBSD: GENERIC.local,v 1.1 1996/09/09 16:37:08 mycroft Exp $
#
#	GENERIC.local -- local additions to the GENERIC configuration
#

options 	CONSDEVNAME="\"com\"",CONADDR=0x2f8,CONSPEED=9600
options 	CONS_OVERRIDE	# Always use above! independent of boot info

#options 	ACPIVERBOSE	# verbose ACPI device autoconfig messages

acpi0 		at mainbus0
#options 	ACPI_PCI_FIXUP		# PCI interrupt routing via ACPI
#options 	ACPI_ACTIVATE_DEV	# If set, activate inactive devices
#options 	ACPICA_PEDANTIC		# force strict conformance to the Spec.
#options	ACPI_DISABLE_ON_POWEROFF	# disable acpi on power off

# ACPI devices
#acpiacad* 	at acpi?		# ACPI AC Adapter
#acpibat* 	at acpi?		# ACPI Battery
acpibut* 	at acpi?		# ACPI Button
#acpiec* 	at acpi?		# ACPI Embedded Controller
#acpilid* 	at acpi?		# ACPI Lid Switch
#acpitz* 	at acpi?		# ACPI Thermal Zone

# Mainboard devices
#com* 		at acpi?		# Serial communications interface
#fdc* 		at acpi?		# Floppy disk controller
#lpt* 		at acpi?		# Parallel port
#npx*		at acpi?		# Math coprocessor
#pckbc*  	at acpi?		# PC keyboard controller
#wss* 		at acpi?		# NeoMagic 256AV in wss mode
---------------------------------------------------------

2. /etc/rc.conf

Both NICs are i82559 revision 8.  As outlined in fxp(4) these NICs
support a receive interrupt mitigation function (known as CPUSaver).
This option can be enabled by setting ``link0'' in /etc/rc.conf as in
this example:

---------------------------------------------------------
[...]
# Add local overrides below
#
hostname="procyon.dmz.local"
defaultroute="192.168.1.1"
clear_tmp=NO
update_motd=NO
ifconfig_fxp0="192.168.1.2 link0 up"
ifconfig_fxp1="192.168.2.1 link0 up"
sshd=YES
powerd=YES
wscons=YES
---------------------------------------------------------

Hope that these files will help people that wants to get the
best from the hardware on this server.

Best regards,

Igor.