This site has most of the relevant portions of the Chinese site up:
http://www.bouweenpc.nl/nieuws/hardware/review-nvidia-geforce-gtx-680-uitgelekt
Translation link via Google Translate:
http://translate.google.com/transla...dware/review-nvidia-geforce-gtx-680-uitgelekt
"New Adaptive VSync technology
NVIDIA, on the other hand, made ​​for the actual operation of fluency of the game is optimized and to promote the new Adaptive VSync VSync setting are gamers, open the main purpose is to reduce the graphics card output image is generated in different fps too fast or too slow situations, and the output frame rate is locked in with the mainstream display screen 60fps. However, the image of the actual output of the graphics card will still be due to different scenes within the game for differences between the actual output fps lower than 60fps fps, will be directly reduced to 30 below 30fps is reduced to 20fps.
In fact, such cases are quite common, and convert 60fps to 30fps of the screen will significantly slow the beating, which greatly affect the fluency of the game, the new Adaptive VSync just solve the problem, when the Adaptive VSync enabled, the system automatically detection of the actual operation fps than 60 VSync will open a locked 60fps output frames, such as less than 60 will be automatically VSync turn off and running to the actual output frames to reduce all of a sudden dropped to 30fps from 60fps is the emergence of slow beat, can be very useful."
Yes, that sounds good to me. I like VSYNC but hate the bouncing back and forth between 30 and 60 in some games.