From: Muhammad Panji <sumodirjo at gmail.com> > I have an onboard Realtek RTL8111/8168B NIC. from lspci -vv : > 02:00.0 Ethernet controller: Realtek Semiconductor Co., Ltd. > RTL8111/8168B PCI Express Gigabit Ethernet controller (rev 02) > It is detected, but why the speed is always 100Mbps, already change > cable but still no luck. I use ethtool and from the output it seems > that system know that this NIC support gigabit speed : > have change the driver r8169 with r8168 and follow the guide on CentOS > wiki http://wiki.centos.org/AdditionalResources/HardwareList/RealTekRTL8111b > but still it only get 100Mbps speed. Same controller here... and I always get downgraded to 100Mbps... I am using kmod-r8168-8.025.00-1 I have other PCs connected to the same switch and they are in 1000Mbps... # ethtool eth0 Settings for eth0: Supported ports: [ TP ] Supported link modes: 10baseT/Half 10baseT/Full 100baseT/Half 100baseT/Full 1000baseT/Full Supports auto-negotiation: Yes Advertised link modes: 10baseT/Half 10baseT/Full 100baseT/Half 100baseT/Full 1000baseT/Full Advertised auto-negotiation: Yes Speed: 100Mb/s Duplex: Full Port: Twisted Pair PHYAD: 0 Transceiver: internal Auto-negotiation: on Supports Wake-on: pumbg Wake-on: g Current message level: 0x00000033 (51) Link detected: yes I tried: # ethtool -s eth0 speed 1000 duplex full autoneg off advertise 0x020 but auto-negotiation stays on and I only get 100Mbps... I tried: # ethtool -s eth0 duplex full autoneg off advertise 0x020 auto-negotiation is off but nothing change... JD