Flat panel scaling on external device

[Vortex]

Hi everyone,

I have my LCD Monitor hooked up to my notebook via HDMI. In the NVIDIA Control Panel I went to "Set up multiple displays" and selected "Only use one display" and selected the external monitor from the drop-down box, thus disabling the internal display of the notebook.

Now when I go to "Change flat panel scaling" everything is grayed out. I cannot adjust flat panel scaling for the external monitor. In dual-view mode I can only change the setting for the internal display.

This works fine on Linux on the same machine, at least in single-display mode so I refuse to believe that it's not possible. Looks more like a bug in the NVIDIA Control Panel to me. Or am I doing something wrong?

How can I enable NVIDIA scaling on the external monitor?