Texture options for displacement - color ramp

I can’t make color ramp working in “texture” tab. Ex, i want to crush some detail on texture for displacement purposes , when enable ramp it ignores texture and gives me solid white. Am i doing it wrong or don’t understand something. Color ramps sure work in any other part of blender, but not in texture tab.

Pictures on and off


Turn Clamp on also, then play with the brightness and contrast values

It didn’t work, but turning on alpha calculate worked. So its solved now. Thanks regardless. (pretty sure its a bug tho)