I have a weird one. I have a 1721 loaded with a very recent IOS image. FA0 is pointing to the internet and is configured for DHCP. My WIC-4ESW is on the private LAN. The LAN has a four port 3Com gigabit consumer switch. My PC and my router are plugged into the 3Com. The router boots fine and is ready for connections. But it drops straight to ROMMON the moment I turn on OR off my PC. I then have to reboot the router for it to be okay. The motherboard of the PC is a D875PBZ. Suggestions?