Hello, recently i got a vanilla install on my Dell Vostro 1520, everything seems fine (except for the wireless card and the volume control). For the wireless card problem i'll buy a WiFi dongle, but the sound problem i don't know how to solve it...My Mac OS X installation has sound but i cant lower or rise it through the volume control in the panel, please help me, how i can solve this?

I installed Mac OS X through the iBoot method and i installed the Voodoo HD(Universal) driver.
Greetings.