Questions
Q1
Will A68N-5000 support Dolby HD and DTS HD MA output through HDMI® port?

Yes, both Dolby HD and DTS HD MA will support by motherboard's HDMI® port.

Also it could support by add on VGA card's HDMI® port if the HDMI® is version 1.3 or higher.

However, it will need an external decoder for these two audio formats to work.