Ok, j'ai aussi la carte onboard 3Com Gigabit lan qui tourne et qui est configurée.....
[code:1:b9f9f034b1]
eth0&#58; 3Com Gigabit LOM &#40;3C940&#41;
      PrefPort&#58;A  RlmtMode&#58;Check Link State

eth0&#58; network connection up using port A
    speed&#58;           100
    autonegotiation&#58; yes
    duplex mode&#58;     full
    flowctrl&#58;        none
    irq moderation&#58;  disabled
    scatter-gather&#58;  enabled
[/code:1:b9f9f034b1]

je demonte l'autre carte