Open a Web browser and go to HP Software & Driver Downloads page.
Enter the model number of your HP or Compaq computer into the field provided, for example, m9390d.
Select the operating system, Windows Vista or Vista 64-bit, if an operating system selection page opens.
Select NVIDIA GeForce 9500 GS Video BIOS Update and follow the instructions to download and install the driver (sp37497).HDMI audio should be heard after selecting HDMI as the default audio device from Windows Vista sound properties (available from Control Panel).
HP Customer Support
HP and Compaq Desktop PCs - No Audio with HDMI (NVIDIA GeForce 9500GS Graphics Card)
This document pertains only to HP and Compaq PCs with an NVIDIA GeForce 9500GS graphics card.
There is no audio when using an HDMI connection from an NVIDIA GeForce 9500GS graphics card.
To resolve this problem, download and install sp37497 from HP.com:
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