Acer Extensa 4630z laptop sound/audio driver problem Windows 7 32bit  

My Acer Extensa 4630z laptop sound/audio driver on Windows 7 Ultimate 32 bit not working. It was working few days before but stopped suddenly. I tried all the audio driver from Download Drivers and Manuals | Acer Official Site. By the way there is no audio driver for Windows 7 so I even tried Vista audio driver from same site but no luck. I tried Driver Pack solution 14 but it could not detect audio. I even installed new Windows 7 ultimate 32 bit but no luck it found automatically many drivers but not audio. Please help me figure out audio problem. I tried installing Realtek driver for Vista and Windows 7, no luck either. thanks

Yes, I have installed almost all the drivers from Acer Driver Support site, but still could not fixed the problem.