Read on if Windows 7 installed but no sound, can only select Realtek Digital Output in playback devices which uses Rear panel Optical Jack.
If you have installed Windows 7 64bit Ultimate on your system and have no option to select your speakers but have installed the latest drivers from Realtek.
Go here http://www.realtek.com.tw/downloads/downloadsview.aspx?langid=1&pnid=14&pfid=24&level=4&conn=3&downtypeid=3&getdown=false - You may need to click accept a couple of times first.
Today I installed windows 7 and had the above problem and had already gone to the Realtek website and followed the download links to the latest AC'97 Codec but for some reason that logical link offers out of date drivers which didn't work dated back in March 09.
I Googled the problem and found a forum here http://www.sevenforums.com/sound-audio/3756-latest-realtek-hd-audio-driver-version.html which links to the hidden page with the correct AC'97 drivers.
The driver I am successfully using is: Vista, Windows7 Driver (32/64 bits) Driver only (ZIP file) R2.30
