i think nvidia no longer updating ntune. upon quick google on ntune it leads me to this link:http://www.nvidia.com/object/ntune_5.05.54.00.html
the software are dated on 2007. on older forceware you can overclock your gpu from nvidia control panel but going forward nvidia drop the feature from forceware but and introducing ntune which is not only to monitor nvidia gpu but also nvidia chipset. with no update since 2007 i don't think nvidia really cares about ntune anymore. right now most people are using 3rd parties solution to monitor and overclock nvidia gpu.