I have a small fileserver. It's just used for myself and my wife for convenience. It's also used as a media server for our television.
I'm running it with Ubuntu 8.10 (Intrepid) on it.
It's running an Intel Atom motherboard as shown here:
The product spec sheet says the following about the on-board NIC:
The LAN, based on the RealTek RTL8111C Ethernet Controller, provides the following
functions: 10/100/1000 Mb/s Gigabit Ethernet LAN
I also tossed on a gigabit NIC as shown here:
NetGear GA311 Ver.A1
Both of these NICs connect ONLY at 100 mbit and I don't know why. At first the secondary NIC was connecting at gig speed. The motherboard network interface I'm not sure of at the start because it was only connected to a 100 mbit device on the other side.
The Netgear is connected to a Netgear 5 port gig switch. The switch has 2 indicator LEDs where if one LED is lit, it's 100 mbit. If both are lit, it's 1 gbit connection.
Transfer speeds originally were at 50 MB/sec when it was up on gigabit, limited only by the hard drive in the machine.
Transfer speeds with 100 mbit are as expected, 10-12 MB/sec.
The motherboard interface is using a Realtek RTL8111C chip.
The Netgear NIC uses a Realtek RTL8169 chip.
Can someone help me get these network interfaces connecting at gig speeds?