By default, Intel® adapters auto-negotiate speed and duplex settings. If the adapter is unable to establish connectivity using auto-negotiation, you might need to manually configure speed and duplex settings on the adapter and link partner. For example, if a switch does not support auto-negotiation or is configured with a specific speed and duplex, you must manually configure the adapter speed and duplex to match the switch settings.
To set speed and duplex:
From the Speed tab, choose one of the following option buttons:
Auto-negotiate best speed
10 Mbps half duplex
10 Mbps full duplex
100 Mbps half duplex
100 Mbps full duplex
1000 Mbps full duplex
To ensure communication, verify that the link partner supports the forced setting.
CAUTION: In nearly all cases you should leave auto-negotiation enabled. With auto-negotiation enabled, the adapter negotiates speed and duplex with its link partner. With auto-negotiation disabled, the adapter is forced to the specified speed and duplex setting. When disabling auto-negotiation, make sure the link partner can operate at the specified speed and duplex. If the link partner cannot operate at the adapter's forced setting, communication cannot be established between the adapter and the link partner.
Click Apply.
Restart your computer if prompted.
The speed and duplex setting is now configured for the adapter.