Hi LouiseCA,
To determine the sound card installed on your computer you may follow any of the below method:
Method 1:
Show in hidden devices in device manager:
a. Click Start, click Run, and then type devmgmt.msc.
b. Click on View tab
c. Select show hidden devices
d. Search for the sound device.
Method 2:
a. Click Start, click Run, type msinfo32.exe in the Open box, and then click OK.
b. Expand Components
c. Point to sound devices
d. Check for the manufacturer of the sound device.
You may refer the below link to know the hardware and software vendor contact information:http://support.microsoft.com/gp/vendors/en-us
You may refer the below link to install sound card: Install or remove a sound card (Holds good for windows XP):http://windows.microsoft.com/en-US/windows-vista/Install-or-remove-a-sound-card
Regards:
Samhrutha G S - Microsoft Support.
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