We have an Intel Pro 1000 PT Dual Port Server Adapter running on a WIN2K8 box housed in an offsite colo.

I recently learned that the auto-negotiated link speed is 100Mbps. When I run the diagnostic test provided by the Device Manager > [Card] > Properties window, it says that the Network Adapter is set to auto negotiate the link speed but that "...1000 Mbps has not been chosen as one of the possible speeds."

I don't see anywhere in the properties tabs that suggest any config setting like "Available link speeds."

So, this is kind of 2 questions:

  1. Is it possible that if I change the link speed from auto negotiate to 1000Mbps the network card will cease to work until I go onsite and change it back?
  2. Does anyone know how I can configure 1000Mbps to be one of the available link speeds for the auto negotiation?

Thanks in advance.


Step 1: Ensure that the switch you're plugged into is really gigabit.

Step 2: Be prepared to travel to the colo to fix this should it go dark.

My guess is that the switch port is not allowing gigabit.

  • In addition to checking the switch is gig, you might also want to check that you have good wiring. – Zoredache Nov 24 '09 at 19:23

Not an answer to your problem, but Joel Spolsky has experienced this problem...

Five whys: http://www.joelonsoftware.com/items/2008/01/22.html


I'm using an Intel Pro 1000/MT NIC on W2K8 and to set the link speed you need to go to the properties of the NIC, click the Configure button, select the Advanced tab, select the Link Speed & Duplex item and set it to 1000Mbps Full. Note that there are no options for half duplex for GB speed. Be prepared to drive to the data center to set it back if it loses connectivity after making the change. My guess, as others have said, is that the switch port is set to 100Mbps.

  • Sorry for being such a noob - but how I don't know what a switch port is or how to determine its speed. Is that something that I would have to ask my cabinet provider. I am just handed an ethernet chord and told to use specific DNS address info. – fordareh Nov 26 '09 at 2:37

Do you have the latest driver for the NIC? Is it the Intel provided driver or a Windows driver?

  • It's funny that you should ask - one box has the windows driver and one box has the latest Intel driver, however the problem is the same on both boxes. – fordareh Nov 26 '09 at 2:50
  • OK - so our colos site it says the provide a 1000Mbps connection from their router to the cabinet and 100Mbps connections to each box in the cabinet. Should that lead me to believe that I am on a 100Mbps switch port? – fordareh Nov 26 '09 at 2:56

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