No sound after reinstalling XP

Hello
this is the system details

OS Name Microsoft Windows XP Professional
Version 5.1.2600 Service Pack 2 Build 2600
OS Manufacturer Microsoft Corporation
System Name NIC-05C1A4BDF97
System Manufacturer Hewlett-Packard
System Model HP Pavilion dv9700 Notebook PC
System Type X86-based PC
Processor x86 Family 15 Model 104 Stepping 2 AuthenticAMD ~1908 Mhz
Processor x86 Family 15 Model 104 Stepping 2 AuthenticAMD ~1908 Mhz
BIOS Version/Date Hewlett-Packard F.25, 11/29/2007
SMBIOS Version 2.4
Windows Directory C:\WINDOWS
System Directory C:\WINDOWS\system32
Boot Device \Device\HarddiskVolume1
Locale United States
Hardware Abstraction Layer Version = "5.1.2600.2180 (xpsp_sp2_rtm.040803-2158)"
User Name NIC-05C1A4BDF97\NIC
Time Zone India Standard Time
Total Physical Memory 2,048.00 MB
Available Physical Memory 1.50 GB
Total Virtual Memory 2.00 GB
Available Virtual Memory 1.96 GB
Page File Space 3.85 GB
Page File C:\pagefile.sys

after formatting and reinstalling windows XP,the sound is not working anymore..kindly help