The sound driver is :

ATI Function Driver for High Definition Audio - ATI 791A

you can manually update the driver from the ATI graphic video driver.


The 7 Unknow Drivers is :

Direct Application Launch Button

you have to manually update the driver from the driver folder.

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I managed to install the driver for xp and run smoothly, but there's still a problem: I can't use Fn key to adjust the screen brightness, but other Fn key work properly.

anyone find the solution?

sp39425 - HP Quick Launch Buttons (WinXP)
sp38358 - HP Quick Launch Buttons (WinVista)

tried these two still cannot.

For ATI 791A, you can download the latest driver here:

http://www.filehippo.com/download_ati_catalyst_xp/