No audio devices detected

So, after upgrading to Windows 10, my computer no longer detects any audio devices.

Device manager only detects nvidia hd audio
Playback devices only detects nvidia hd audio

After installing realtek drivers, realtek is nowhere to be found - no icon in system tray, no realtek device in device manager etc.

USB headphones work fine, just dont have any support for rear panel audio jacks, have disconnected front panel audi connector, installed fress win10 copy, still nothing

First step, reinstall the Intel motherboard chipset drivers. Then restart the PC and check after Windows has started to see if the generic, basic function, High Definition Audio Driver is installed for the sound. If it is and the sound works you can then reinstall the Realtek drivers (if Windows doesn't install that instead of the HD Audio).

USB headphones work as they do not use the PC audio, they take digital data and do the audio conversion inside the headset.

Installed chipset drivers, rebooted, absolutely no change whatsoever

Under sound, video and game controllers the only device present is Nvidia HD audio

If I go under system devices there are two hd audio controllers present, one being the nvidia one..

Have tried updating, uninstalling, reinstalling the other one, all to no avail

I have another user, on the Windows 7 forum, that upgraded to Win 10 and lost audio. They went back to Win 7 but still lost, similar to yours. Unfortunately the next step for that user is a clean Win 7 install. I hate to tell you that too, but something to consider.