Just for the record, I set up Windows 7 on an Asus M4N78 Pro based system a couple of days ago. It installed the NIC driver automatically. Next day I rebooted and the network wasn't connected. After a bit of head scratching, I tried disabling the on-board NIC via the BIOS and fired up the system. I then did a Restart, went back into the BIOS and enabled the on-board NIC again. When Windows 7 started, the network connection was back working OK.