In Windows you can use the driver “Advanced properties” to change the Link Speed
To change Link speed in Linux use the command lines below
sudo ethtool –s <ethX> autoneg off speed Y
Y = 100/1000/25000/5000/10000
To re enable autoneg:
sudo ethtool –s <ethX> autoneg on
Only “Full Duplex” mode is supported by 10GbE standard.