ZBrushCentral

Displacement map looks broken in zbrush,i need help!

why my displacement map looks like this in zbrush,
dis1.png
it’s a clean tilted map exported from PS with Jpg format
dis3.png
my model UV is full unfolded,no any clipping
even when i map it on another new model ,it is still broken
dis2.png
anyone could help me ? im waiting