My Pc have both  Windos Xp and Windows 7 , when i USE in xp i can here sound but when i use Windows 7 I can't here any sound but it's seem like the audio playing ,its show the wave and the song is run but no any sound come out , i asked someone said because of driver and i think so, when i go to Device Manager and click on Sound Videoo and Game Controllers it show "High Definition Audio Device" and there are no any yellow or red mark , when i double click on tt in the GENERAL in the Device Status say The device is working properly , when i click on the driver button it doesn't show the name of the soundcard when i click on the Update driver button and click automatic update it say "The best driver solfware for your deice is already installed" and when i play audio it still no sound so what's a problem anyone know PLEASE tell me , my soundcard is name Sound Max Integrated Digital ,is that the name of sound card and if it's not where can i check that what's the name of sound card i'm using ? anyone know tell me please>>>>well I haven't played with windows 7 yet as I don't have another comp to install it on so I can't really tell you how to fix your problem but I can say that windows 7 is still in Beta so some things may just not WORK.Did you re-install your drivers in Windows 7 ? ?
This has to be done before your devices will work properly...My audio Drivers worked just FINE "out of the box" so to speak.

Does your motherboard fully support Windows Vista?

If it does, try to install the vista based drivers off the motherboard install disk.He hasn't been back in 5 days...
But great advice.