Same problem here -- at two different sites. It looks like AMT forces the NIC to 10Mbps when the system is off and allows autonegotiation during boot. If the KVM session is active, the NIC remains at 10Mbps.
If you initiate a connection that 10mb half duplex is maintained until the connection is dropped (where the NIC will when re-auto negotiate the link at a higher speed).
If that's the case, is there a way to force the NIC to autonegotiate at 100.0 Mbps down at the hardware/BIOS level? I know the NIC goes into powersaving mode @ 10.0 Mbps to listen for magical packets (WOL) but I always have to reboot the machine every time to negotiate at the highest possible speed. I'm trying to create a remote server setup with no necessary intervention at the computer's site. Can this be looked into on the DQ57TM mobo?
There's no way to force it to a faster speed when it's off or sleeping. And, once you have a KVM (or SOL or IDER) session open it can't renegotiate. If it did, most likely the connection would drop.
What you could do instead is use a tool likeRemote Power Control Util to perform the wake up. This way it wakes w/o KVM connected, allowing it to negotiate a faster speed. Once its up, then connect with VNC Viewer Plus.