1. Maybe you din't connect the hd audio on the motherboard or add the jumper or...
2. You need to force windows to take the driver you give (or windows is gona install the generic one an not the good)
here the step, unzip you driver into a folder (if is a installer .exe just unpack it into a folder) on you desktop
in device manager right click hd audio (or whatever name), right click an click update driver software
select browse my computer for the driver
click let me pick from a list
click have disk
browse into you folder containing the driver
install the good one
done an restart
Hope it help