Strobelight - LightBoost Utility for AMD/ATI and NVIDIA

[ToastyX]

You're describing two different things. Which is happening under what circumstances? What happens when you install the default "120 Hz (strobed)" and "121 Hz" refresh rates?

If "Strobing off" is grayed out, that means there aren't any non-strobed refresh rates available to the program. If you did have a non-strobed refresh rate installed, then something is preventing the installed refresh rates from working.

If it's not grayed out, what happens when you choose it? Does the screen black out like it's changing resolutions or does nothing happen at all? If nothing happens, that's really weird.

First, make sure GeForce Experience is not installed. GeForce Experience is known to trigger a bug in the NVIDIA driver that can cause problems with installed refresh rates. Samsung Magician also triggers the same bug in the NVIDIA driver when it scans for hardware on startup. There might be other programs that trigger the same problem.

Second, check the device manager under display adapters and make sure there are no mirror drivers or anything other than your video card. Mirror drivers create virtual devices that can interfere with installed refresh rates.

After doing that, are the installed refresh rates available in both the NVIDIA control panel and the Windows screen resolution settings? If so, does switching between 120 Hz and 121 Hz do anything?