Thanks for all the replies - it took hours to read them all. So actually this router doesn't support gigabit ethernet, only 10/100.

Model : Archer C2 750 Hardware Version : Archer C20 v1 Firmware Version : 0.9.1 2.1 v0044.0 Build 151120 Rel.35051n ISP : TEO When connecting directly to fiber internet box i get 300+ Mbps. Ethernet...