Gigabit or not? SiS 190 integrated ethernet.

[Peter Sabaini]

On Saturday 24 November 2007 16:58:15 Neil Woolford wrote:
> I have an AMD Athlon based motherboard, with a built-in pci ethernet
> adaptor that reports itself as a SIS 190 Gigabit ethernet adaptor.
>
> However, when I connect it to a gigabit switch, it is reported (by the
> status led) as a 10/100 device, which is indeed the speed it is clearly
> running at.

A guess -- the gigabit switch is reporting the actual speed the network is 
running at, not what the NIC supports. 

What does ethtool say? Eg. here:

# ethtool eth0
Settings for eth0:
        Supported ports: [ MII ]
        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: MII
        PHYAD: 0
        Transceiver: external
        Auto-negotiation: on
        Supports Wake-on: g
        Wake-on: d
        Link detected: yes

So its a gigabit port alright, but it autonegotiated a 100Mbit/s connection 
with my switch. AFAIK many switches operate in an all-or-nothing fashion, ie. 
if one of their endpoints is 100BASE-TX it will downgrade all ports to 
100BASE-TX

Note also that 1000BASE-T is sensitive to cabling, so even if standard Cat5 
cable should be supported, in practice you'll often have to upgrade to get 
full speeds (eg. Cat6 / Cat6e)

HTH,
peter.


> The computer is running an Ubuntu Gutsy system, updated to current.
>
> Is there any kind of specialised driver or non-default configuration needed
> to get Gigabit speeds out of this adaptor, or is it just misnamed?
>
> Neil