No multimedia audio installed

Hello,
I installed Windows 7 on my Dell Latitude D610 Laptop and everything works fine but my sound. I tried to download drivers but when I went into Device Manager it tells me that there is no multimedia audio conttoller installed and there is a yellow "x" on the cound image. However, I initially had XP on my laptop and the sound worked. I did not keep XP but did a custom install for windows 7 because I did not have any files or data that I needed to keep. I went to Driver Finder to download the drivers still no sound. Please help, I am at my wit's end. Thanks