unable to activate the network embeded adapter..grrr

Hi evrybidy,

Hope some will have some clues cause I'm geting nervous.

This PC is runnig XP pro, probably well patched ( ... ) BIOS is
Version du BIOS/Date Phoenix Technologies, LTD 6.00 PG, 01/11/2002
from NVIDIA
Modèle AWRDACPI
It's a home hand assembled machine based over a ZENITH 7njs mother board,
meaning it's including an NVIDIA ethernet 10/100 chip ( NVIDIA nForce MCP
Networking Controller )


this hardware is automaticaly set to :

Bus PCI 0, périphérique 4, fonction 0, full auto nego, and, I cannot change
the "Wakeon lan From poweroff" to disable (this is always enable, even If I
change it - that looks to be correctly set- the next boot it switched back
to enable.
At the same time the other tab " power management " says : "allow the
computer to switch off this peripheral " is NOT checked.

This is the first question may be linked to the pb:

But the very bad issue comes from the fact, at the very second the adapter
is activated (manually or because I just plugged the RJ45 wire to the hub)
then the PC cold reboot.

I made it run during 10 min one time (after an infinite number of reboot )
to acces the Linksys router but can find how to do this again.

I suspect a harware conflict BUT nothing seems to be manually reachable.

Help please

Thank you