[Ubuntu-BR] Por favor me ajudem!!! Não consigo conectar à internet

[Felipe Eduardo Silva Sampaio]

(Re)instalei o Ubuntu hoje(8.04) mas não consigo de jeito nenhum acessar à
internet. Meu modem é roteado e toda vez que eu instalava uma nova versão do
ubuntu, a rede já funcionava sem eu precisar configurar nada, mas dessa vez
não estou conseguinto e não sei o motivo. Procurei na net mas nada que me
ajudasse. Segue algumas informações caso sirva.

Placa mãe: Gigabyte GA-945GCM-S2L

O que apareceu quando digitei no terminal lspci:(um dos poucos comandos que
sei)

00:00.0 Host bridge: Intel Corporation 82945G/GZ/P/PL Memory Controller Hub
(rev 02)
00:01.0 PCI bridge: Intel Corporation 82945G/GZ/P/PL PCI Express Root Port
(rev 02)
00:1b.0 Audio device: Intel Corporation 82801G (ICH7 Family) High Definition
Audio Controller (rev 01)
00:1c.0 PCI bridge: Intel Corporation 82801G (ICH7 Family) PCI Express Port
1 (rev 01)
00:1c.1 PCI bridge: Intel Corporation 82801G (ICH7 Family) PCI Express Port
2 (rev 01)
00:1d.0 USB Controller: Intel Corporation 82801G (ICH7 Family) USB UHCI
Controller #1 (rev 01)
00:1d.1 USB Controller: Intel Corporation 82801G (ICH7 Family) USB UHCI
Controller #2 (rev 01)
00:1d.2 USB Controller: Intel Corporation 82801G (ICH7 Family) USB UHCI
Controller #3 (rev 01)
00:1d.3 USB Controller: Intel Corporation 82801G (ICH7 Family) USB UHCI
Controller #4 (rev 01)
00:1d.7 USB Controller: Intel Corporation 82801G (ICH7 Family) USB2 EHCI
Controller (rev 01)
00:1e.0 PCI bridge: Intel Corporation 82801 PCI Bridge (rev e1)
00:1f.0 ISA bridge: Intel Corporation 82801GB/GR (ICH7 Family) LPC Interface
Bridge (rev 01)
00:1f.2 IDE interface: Intel Corporation 82801GB/GR/GH (ICH7 Family) SATA
IDE Controller (rev 01)
00:1f.3 SMBus: Intel Corporation 82801G (ICH7 Family) SMBus Controller (rev
01)
01:00.0 VGA compatible controller: nVidia Corporation GeForce 8400 GS (rev
a1)
03:00.0 Ethernet controller: Realtek Semiconductor Co., Ltd. RTL8111/8168B
PCI Express Gigabit Ethernet controller (rev 02)
-- 
Felipe Sampaio