Originally Posted by Balsagna
EDIT: Installed the INF you provided as well as tried uninstalled Geforce Experience. The test site linked in the OP still does not go above 60hz nor does TF2 - Everything else I have tested against is working fine at 120hz.
Try rebooting if you haven't already. You don't need to worry about GeForce Experience if you're using the NVIDIA control panel.
I noticed someone told you to disable desktop composition. The test site requires desktop composition to be enabled to work properly, while Refresh Rate Multitool requires it to be disabled (which isn't an option in Windows 8). If you have a second monitor connected running at 60 Hz, that can cause the browser to synchronize at the wrong refresh rate.
If you're not using CRU anymore, run reset-all.exe and reboot to remove any EDID overrides that might be left over.