I recently purchased a LINKSYS SE4008 WRT 8-PORT GIGABIT ETHERNET SWITCH and I am having issues with the onboard NIC and this device. The device is an unmanaged plug and play device. The NIC flaps, drops connection entirely, and reverts to 100 Mbps when connected to the switch. I first tried a different cable (pre-fab) and it didn't fix it. I tried a 3rd cable and it didn't fix it either. The issue seems to be the negotiation of speed/duplex with the switch. Both auto and hard coding to 1 Gbps full duplex does not work correct. I swapped the switch with another (of the same switch) and same issue. Everything else plugged into the switch / ports work great. I updated the drivers to the latest and greatest, still doesn't work. As a work around, I plugged my old switch into my new switch and it's fine now. So... any thoughts? Maybe it's a setting in the onboard NIC the switch doesn't like?