No the newer perfectly working on is a HP Zbook G5, another is an Asus G74sx. I Don't know if its beacause the Asus has an older ethernet card but it definetely supports gigabit speeds.
I have 2 laptops, one via ethernet gets 870 Mbp/s download via speedtest while the other fluctuates between 150/450 Mbp/s. To make sure it wasnt a placebo effect I brought the malfunctioning laptop to the exact same ethernet cable and did a speedtest, as expected the working laptop got 870...