I've managed to install macOS Sierra on a Dell Precision T1600 Workstation (Xeon E3-1270, AMD HD6570 graphics card). The HDMI sound works perfectly; but the onboard sound does not work. I'm a bit disappointed that the AppleHDA requests has been pinned. But I would be grateful if one of the sound experts would take a look at the attached files.
The strange thing is that HDMI sound works with AppleHDA; and the onboard sound works with Voodoohda: but not concurrenly.