Désole de ne pas avoir été assez précis 
Voici les infos demandées :
Version du noyau : 2.6.32-5-amd64
Retour de lspci :
00:00.0 Host bridge: ATI Technologies Inc RD890 PCI to PCI bridge (external gfx0 port B) (rev 02)
00:00.2 Generic system peripheral [0806]: ATI Technologies Inc Device 5a23
00:02.0 PCI bridge: ATI Technologies Inc RD890 PCI to PCI bridge (PCI express gpp port B)
00:09.0 PCI bridge: ATI Technologies Inc RD890 PCI to PCI bridge (PCI express gpp port H)
00:0a.0 PCI bridge: ATI Technologies Inc RD890 PCI to PCI bridge (external gfx1 port A)
00:11.0 SATA controller: ATI Technologies Inc SB700/SB800 SATA Controller [AHCI mode] (rev 40)
00:12.0 USB Controller: ATI Technologies Inc SB700/SB800 USB OHCI0 Controller
00:12.2 USB Controller: ATI Technologies Inc SB700/SB800 USB EHCI Controller
00:13.0 USB Controller: ATI Technologies Inc SB700/SB800 USB OHCI0 Controller
00:13.2 USB Controller: ATI Technologies Inc SB700/SB800 USB EHCI Controller
00:14.0 SMBus: ATI Technologies Inc SBx00 SMBus Controller (rev 42)
00:14.2 Audio device: ATI Technologies Inc SBx00 Azalia (Intel HDA) (rev 40)
00:14.3 ISA bridge: ATI Technologies Inc SB700/SB800 LPC host controller (rev 40)
00:14.4 PCI bridge: ATI Technologies Inc SBx00 PCI to PCI Bridge (rev 40)
00:14.5 USB Controller: ATI Technologies Inc SB700/SB800 USB OHCI2 Controller
00:15.0 PCI bridge: ATI Technologies Inc Device 43a0
00:15.1 PCI bridge: ATI Technologies Inc Device 43a1
00:15.2 PCI bridge: ATI Technologies Inc Device 43a2
00:15.3 PCI bridge: ATI Technologies Inc Device 43a3
00:16.0 USB Controller: ATI Technologies Inc SB700/SB800 USB OHCI0 Controller
00:16.2 USB Controller: ATI Technologies Inc SB700/SB800 USB EHCI Controller
00:18.0 Host bridge: Advanced Micro Devices [AMD] Family 10h Processor HyperTransport Configuration
00:18.1 Host bridge: Advanced Micro Devices [AMD] Family 10h Processor Address Map
00:18.2 Host bridge: Advanced Micro Devices [AMD] Family 10h Processor DRAM Controller
00:18.3 Host bridge: Advanced Micro Devices [AMD] Family 10h Processor Miscellaneous Control
00:18.4 Host bridge: Advanced Micro Devices [AMD] Family 10h Processor Link Control
01:00.0 VGA compatible controller: ATI Technologies Inc Device 6718
01:00.1 Audio device: ATI Technologies Inc Device aa80
02:00.0 USB Controller: Device 1b6f:7023 (rev 01)
03:00.0 SATA controller: JMicron Technology Corp. JMB362/JMB363 Serial ATA Controller (rev 02)
03:00.1 IDE interface: JMicron Technology Corp. JMB362/JMB363 Serial ATA Controller (rev 02)
04:06.0 Multimedia audio controller: Creative Labs SB X-Fi
04:0e.0 FireWire (IEEE 1394): VIA Technologies, Inc. VT6306/7/8 [Fire II(M)] IEEE 1394 OHCI Controller (rev c0)
05:00.0 Ethernet controller: Realtek Semiconductor Co., Ltd. RTL8111/8168B PCI Express Gigabit Ethernet controller (rev 06)
06:00.0 USB Controller: Device 1b6f:7023 (rev 01)
Retour de lsusb :
00:00.0 Host bridge: ATI Technologies Inc RD890 PCI to PCI bridge (external gfx0 port B) (rev 02)
00:00.2 Generic system peripheral [0806]: ATI Technologies Inc Device 5a23
00:02.0 PCI bridge: ATI Technologies Inc RD890 PCI to PCI bridge (PCI express gpp port B)
00:09.0 PCI bridge: ATI Technologies Inc RD890 PCI to PCI bridge (PCI express gpp port H)
00:0a.0 PCI bridge: ATI Technologies Inc RD890 PCI to PCI bridge (external gfx1 port A)
00:11.0 SATA controller: ATI Technologies Inc SB700/SB800 SATA Controller [AHCI mode] (rev 40)
00:12.0 USB Controller: ATI Technologies Inc SB700/SB800 USB OHCI0 Controller
00:12.2 USB Controller: ATI Technologies Inc SB700/SB800 USB EHCI Controller
00:13.0 USB Controller: ATI Technologies Inc SB700/SB800 USB OHCI0 Controller
00:13.2 USB Controller: ATI Technologies Inc SB700/SB800 USB EHCI Controller
00:14.0 SMBus: ATI Technologies Inc SBx00 SMBus Controller (rev 42)
00:14.2 Audio device: ATI Technologies Inc SBx00 Azalia (Intel HDA) (rev 40)
00:14.3 ISA bridge: ATI Technologies Inc SB700/SB800 LPC host controller (rev 40)
00:14.4 PCI bridge: ATI Technologies Inc SBx00 PCI to PCI Bridge (rev 40)
00:14.5 USB Controller: ATI Technologies Inc SB700/SB800 USB OHCI2 Controller
00:15.0 PCI bridge: ATI Technologies Inc Device 43a0
00:15.1 PCI bridge: ATI Technologies Inc Device 43a1
00:15.2 PCI bridge: ATI Technologies Inc Device 43a2
00:15.3 PCI bridge: ATI Technologies Inc Device 43a3
00:16.0 USB Controller: ATI Technologies Inc SB700/SB800 USB OHCI0 Controller
00:16.2 USB Controller: ATI Technologies Inc SB700/SB800 USB EHCI Controller
00:18.0 Host bridge: Advanced Micro Devices [AMD] Family 10h Processor HyperTransport Configuration
00:18.1 Host bridge: Advanced Micro Devices [AMD] Family 10h Processor Address Map
00:18.2 Host bridge: Advanced Micro Devices [AMD] Family 10h Processor DRAM Controller
00:18.3 Host bridge: Advanced Micro Devices [AMD] Family 10h Processor Miscellaneous Control
00:18.4 Host bridge: Advanced Micro Devices [AMD] Family 10h Processor Link Control
01:00.0 VGA compatible controller: ATI Technologies Inc Device 6718
01:00.1 Audio device: ATI Technologies Inc Device aa80
02:00.0 USB Controller: Device 1b6f:7023 (rev 01)
03:00.0 SATA controller: JMicron Technology Corp. JMB362/JMB363 Serial ATA Controller (rev 02)
03:00.1 IDE interface: JMicron Technology Corp. JMB362/JMB363 Serial ATA Controller (rev 02)
04:06.0 Multimedia audio controller: Creative Labs SB X-Fi
04:0e.0 FireWire (IEEE 1394): VIA Technologies, Inc. VT6306/7/8 [Fire II(M)] IEEE 1394 OHCI Controller (rev c0)
05:00.0 Ethernet controller: Realtek Semiconductor Co., Ltd. RTL8111/8168B PCI Express Gigabit Ethernet controller (rev 06)
06:00.0 USB Controller: Device 1b6f:7023 (rev 01)
Contenu de /etc/network/interfaces :
[code]# This file describes the network interfaces available on your system
and how to activate them. For more information, see interfaces(5).
The loopback network interface
auto lo
iface lo inet loopback
The primary network interface
allow-hotplug eth0
iface eth0 inet dhcp[/quote]
Contenu de /etc/resolv.conf :
[quote]nameserver 192.168.1.254[/code]
Retour de ifconfig -a :
[code]eth0 Link encap:Ethernet HWaddr 50:e5:49:bd:94:5e
inet adr:192.168.1.16 Bcast:192.168.1.255 Masque:255.255.255.0
adr inet6: 2a01:e35:8b7b:5340:52e5:49ff:febd:945e/64 Scope:Global
adr inet6: fe80::52e5:49ff:febd:945e/64 Scope:Lien
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:128 errors:0 dropped:128 overruns:0 frame:128
TX packets:104 errors:0 dropped:47 overruns:0 carrier:0
collisions:0 lg file transmission:1000
RX bytes:12448 (12.1 KiB) TX bytes:10471 (10.2 KiB)
Interruption:32 Adresse de base:0xe000
lo Link encap:Boucle locale
inet adr:127.0.0.1 Masque:255.0.0.0
adr inet6: ::1/128 Scope:Hôte
UP LOOPBACK RUNNING MTU:16436 Metric:1
RX packets:43 errors:0 dropped:0 overruns:0 frame:0
TX packets:43 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 lg file transmission:0
RX bytes:3170 (3.0 KiB) TX bytes:3170 (3.0 KiB)[/code]
Retour de route -n :
Table de routage IP du noyau
Destination Passerelle Genmask Indic Metric Ref Use Iface
192.168.1.0 0.0.0.0 255.255.255.0 U 0 0 0 eth0
0.0.0.0 192.168.1.254 0.0.0.0 UG 0 0 0 eth0
Voilà Voilà…
Pour info, je passe déjà par wicd pour la config réseau via xfce.