Intel Gigabit NIC not working on Gigabit?!?!?!

Hello all! Maybe one of you have had this problem! I have an Intel DG965WH Motherboard that has a built in Intel 82566DC Gigabit LAN adapter. For the life of me, I cannot get this NIC to work in gigabit mode. I am running Windows 7 Pro x64. If I kick the NIC back to 10/100 it works fine, but not Gigabit. I read somewhere it may have to do with power, but still cannot find any solutions. Any help is greatly appreciated! Thanks!! Kris