nVidia NIC strange crash

hello, I got a following strange problem - I have an MSI board with nforce 3 250gb chipset, and integrated nVidia LAN - everything is working fine, until I do one thing - disable the LAN connection (as I understand it that is the same as disabling the network adapter). Guess what happens? an immediate bluescreen - everytime I do it, tried WinXP and Win 2000 - results very similar. bluescreen says that error occured in the main driver file, (nvlrm.sys or something like that). Actually, after hours and hours of research and misery, I worked out a simple solution - unplugging the cable instead of disabling the NIC - you may ask why is that a problem, but we had a dumb university network, running with some securew2 client enabling 802.11 authentication over EAP protocol or sth. like that, and this "sofisticated" solution never works - when I turned on the PC, it never authenticated corretly with DHCP server, and the only way to connect was to re-enable the LAN connection (that was a problem of many other students). I ASK, DO YOU THINK IT'S A FAULTY HARDWARE, an IRQ PROBLEM or what ? When I use a PCI NIC, there is no problem - but I prefer the on-board one for obvious reasons. thanks for any valuable suggestions.

oh my, I'm really "glad" I'm not the only one in the world having this problem Now as you remind me, it also started when I was installing the drivers or uninstalling the firewall or sth like that, I don't remember exactly, but I believe that it worked fine when I bought the board.. Maybe that is some hidden fault in nVidia's NIC?? I'd really like to see some other people's experiences and opinions.