After wiping out Windows Vista and installing Windows XP Pro SP2 in my Dell Inspiron 1720 I found my self in trouble. I could not find any where in Dell's web site or forums the driver for the sound device for my laptop.
After several hours of search and trying different drivers I found a driver only available in Dell's German Language for the SigmaTel sound card R153908.exe.
You can download it from Dell's website here or you can get it from my online box here.
Just donwload run the file it will extract all the files to a directory default "c:\dell\drivers" and the setup will be launched.