Wondering if you (admin) have gotten around to testing DGDecNV in Windows 8?
Nvidia seems to have released drivers some while ago:
Version 302.82 - WHQL
Release Date Wed Jun 27, 2012
Operating System Windows 8 64-bit.
[RESOLVED] Windows 8
Re: Windows 8
No, I don't have a Win8 system. Please report your results here. 
Re: Windows 8
Will do, might take some time though. Have to create a image backup first in case i can't find a good way of disabling/overriding that metro "interface".
Re: Windows 8
Several users have reported things work fine in Windows 8.