Just an update to this old thread: nVidia still hasn't fixed this issue. New
GeForce driver 337.88 (5/26/14) did not address and fix the problem. It did, however, eliminate my registry tweaks thereby causing serious latencies, cracking audio and video playback problems (YouTube and Media Player).
Maybe it's just not fixable with the GTX 670 card. Who knows. nVidia support basically abandoned all communications in my support ticket since December 2013.
Fortunately, after performing the registry tweaks again, I'm good to go again!