Pb "aucun périphérique audio"

J'ai un problème depuis que j'ai reformater mon ordinateur. Je n'ai plus de son,il y a écrit aucun périphérique audio ni de lecture. J'ai essaye d'installer différents, mais apparemment ce n'est jamais le bon. Pouvez-vous m'aider?
Voici ma configuration. Merci par avance.

Operating System

Windows XP Media Center (build 2600) Service Pack 3
Default web client: Mozilla Firefox
Default email client: Outlook Express
Default newsgroup client: Outlook Express
Antivirus: avast! antivirus 4.8.1335 [VPS 090521-0] 4.8.1335

Motherboard

SMBios version 2.4
Gigabyte Technology Co., Ltd. M68SM-S2L x.x
Bios: Award Software International, Inc. F6 04/16/2008 taille: 512Kb

Chipset

North bridge: NVIDIA GeForce 7025
South bridge: NVIDIA nForce 630a

Processor

AMD Athlon 64 X2 5000+ Brisbane Socket AM2 (940) (@65 nm) 2600 Mhz ( L1I: 2 x 64
Ko, L1D: 2 x 64 Ko, L2: 2 x 512 Ko )

Memory

Physical memory size: 4096 Mo
DDR2 GR800D264L6/2G 2048 Mo PC2-6400 (400 Mhz) (6.0-6-6-18)
DDR2 GR800D264L6/2G 2048 Mo PC2-6400 (400 Mhz) (6.0-6-6-18)

Graphic card

ATI Technologies Inc RV410 [Radeon X700] (512 Mo)
ATI Technologies Inc RADEON X700 SE Secondary (512 Mo)

IDE devices

ST3250824AS 3.AAE (SATA II, 232.88 Go, tampon: 8 Mo)

CDRom

PHILIPS DVD8801 NW02 (DVD+R/DL Recorder)
AA1352S OYP640C 1.0 (DVD-ROM)

Harddrive

ST3250824AS (232.88Go)
Generic USB CF Reader USB Device
Generic USB MS Reader USB Device
Generic USB SD Reader USB Device
Generic USB SM Reader USB Device

PCI/AGP cards

Mass storage
nVidia Corporation:MCP67 IDE Controller
nVidia Corporation:MCP67 AHCI Controller

Network
nVidia Corporation:MCP67 Ethernet

Display
ATI Technologies Inc:RV410 [Radeon X700]
ATI Technologies Inc:RADEON X700 SE Secondary

Multimedia
nVidia Corporation:MCP67 High Definition Audio

Memory
nVidia Corporation:MCP67 Memory Controller
nVidia Corporation:MCP67 Memory Controller

Bridge
nVidia Corporation:MCP67 ISA Bridge
nVidia Corporation:MCP67 PCI Bridge: MCP67 PCI Bridge
nVidia Corporation:MCP67 PCI Express Bridge: MCP67 PCI Express Bridge
Advanced Micro Devices [AMD]:K8 [Athlon64/Opteron] HyperTransport Technology
Configuration: K8 [Athlon64/Opteron] HyperTransport Technology Configuration
Advanced Micro Devices [AMD]:K8 [Athlon64/Opteron] Address Map: K8
[Athlon64/Opteron] Address Map
Advanced Micro Devices [AMD]:K8 [Athlon64/Opteron] DRAM Controller: K8
[Athlon64/Opteron] DRAM Controller
Advanced Micro Devices [AMD]:K8 [Athlon64/Opteron] Miscellaneous Control: K8
[Athlon64/Opteron] Miscellaneous Control

Serial bus
nVidia Corporation:MCP67 SMBus
nVidia Corporation:MCP67 OHCI USB 1.1 Controller
nVidia Corporation:MCP67 EHCI USB 2.0 Controller
nVidia Corporation:MCP67 OHCI USB 1.1 Controller
nVidia Corporation:MCP67 EHCI USB 2.0 Controller