# Configuring Speed and Duplex in Windows*

The methods used to configure Intel® PRO/100 and PRO/1000 adapters differ slightly.

## Configuring Intel® PRO/100 Adapters

The default setting is for auto-negotiation to be enabled. Change this setting only to match the link partner.

1. Open Intel PROSet from either the Control Panel or the System Tray.

2. Click the Speed tab and highlight the desired adapter in the left window.

3. Select the appropriate speed and duplex settings.

4. Click Apply.

## Configuring Intel PRO/1000 Adapters

The default setting is for auto-negotiation to be enabled.

For Intel PRO/1000 fiber adapters, auto-negotiation is the only speed. For other Intel PRO/1000 adapters, change this setting only if you are encountering problems linking to a link partner. In this case, change the settings to match the link partner.

| NOTES: If auto-negotiation is disabled, the adapter will not operate at gigabit speed (1000 Mbps). Per the IEEE specification, gigabit speed is available only in full-duplex. Fiber-based adapters operate only in full duplex, and only at their native speed.

If auto-negotiation is disabled, you can specify a speed and duplex by following the instructions below.

1. Double-click the Intel PROSet icon from the Control Panel or System Tray.

2. Click the Speed tab and highlight the desired adapter in the left window.

3. Press the F1 key. More specific instructions are available in the Intel PROSet Help window.

`Last modified on 2/07/05 8:00p Revision 1`