Qt 56, 150%:
=============

Screens: 2, High DPI scaling: active
# 0 "\\.\DISPLAY1" Depth: 32 Primary: yes
  Geometry: 1920x1080+0+0 (native: 3840x2160+0+0) Available: 1920x1050+0+0
  Virtual geometry: 5760x1200+0+0 Available: 5760x1160+0+0
  2 virtual siblings
  Physical size: 527x296 mm  Refresh: 29 Hz Power state: 0
  Physical DPI: 92.5389,92.6757 Logical DPI: 72,72 (native: 144,144)
  High DPI scaling factor: 2 DevicePixelRatio: 2 Pixel density: 2
  Primary orientation: 2 Orientation: 2 Native orientation: 0 OrientationUpdateMask: 0

# 1 "\\.\DISPLAY2" Depth: 32 Primary: no
  Geometry: 1920x1200+3840+0 Available: 1920x1160+3840+0
  Virtual geometry: 5760x1200+0+0 Available: 5760x1160+0+0
  2 virtual siblings
  Physical size: 518x324 mm  Refresh: 59 Hz Power state: 0
  Physical DPI: 94.1467,94.0741 Logical DPI: 72,72 (native: 96,96)
  High DPI scaling factor: 1 DevicePixelRatio: 1 Pixel density: 1
  Primary orientation: 2 Orientation: 2 Native orientation: 0 OrientationUpdateMask: 0
  
Qt 56, 225%:
=============
  
Screens: 2, High DPI scaling: active
# 0 "\\.\DISPLAY1" Depth: 32 Primary: yes
  Geometry: 1920x1080+0+0 (native: 3840x2160+0+0) Available: 1920x1035+0+0
  Virtual geometry: 5760x1200+0+0 Available: 5760x1160+0+0
  2 virtual siblings
  Physical size: 527x296 mm  Refresh: 29 Hz Power state: 0
  Physical DPI: 92.5389,92.6757 Logical DPI: 108,108 (native: 216,216)
  High DPI scaling factor: 2 DevicePixelRatio: 2 Pixel density: 2
  Primary orientation: 2 Orientation: 2 Native orientation: 0 OrientationUpdateMask: 0

# 1 "\\.\DISPLAY2" Depth: 32 Primary: no
  Geometry: 1920x1200+3840+0 Available: 1920x1160+3840+0
  Virtual geometry: 5760x1200+0+0 Available: 5760x1160+0+0
  2 virtual siblings
  Physical size: 518x324 mm  Refresh: 59 Hz Power state: 0
  Physical DPI: 94.1467,94.0741 Logical DPI: 108,108 (native: 96,96)
  High DPI scaling factor: 1 DevicePixelRatio: 1 Pixel density: 1
  Primary orientation: 2 Orientation: 2 Native orientation: 0 OrientationUpdateMask: 0

Qt 55, 150%:
=============
  
  Screens: 2
# 0 "\\.\DISPLAY1" Depth: 32 Primary: yes
  Geometry: 3840x2160+0+0 Available: 3840x2100+0+0
  Virtual geometry: 5760x2160+0+0 Available: 5760x2100+0+0
  2 virtual siblings
  Physical size: 527x296 mm  Refresh: 29 Hz
  Physical DPI: 185.078,185.351 Logical DPI: 144,144
  DevicePixelRatio: 1 Primary orientation: 2
  Orientation: 2 Native orientation: 0 OrientationUpdateMask: 0

# 1 "\\.\DISPLAY2" Depth: 32 Primary: no
  Geometry: 1920x1200+3840+0 Available: 1920x1160+3840+0
  Virtual geometry: 5760x2160+0+0 Available: 5760x2100+0+0
  2 virtual siblings
  Physical size: 518x324 mm  Refresh: 59 Hz
  Physical DPI: 94.1467,94.0741 Logical DPI: 96,96
  DevicePixelRatio: 1 Primary orientation: 2
  Orientation: 2 Native orientation: 0 OrientationUpdateMask: 0

Qt 55, 225%:
=============

  Screens: 2
# 0 "\\.\DISPLAY1" Depth: 32 Primary: yes
  Geometry: 1920x1080+0+0 Available: 1920x1035+0+0
  Virtual geometry: 2880x1080+0+0 Available: 2880x1035+0+0
  2 virtual siblings
  Physical size: 527x296 mm  Refresh: 29 Hz
  Physical DPI: 92.5389,92.6757 Logical DPI: 108,108
  DevicePixelRatio: 2 Primary orientation: 2
  Orientation: 2 Native orientation: 0 OrientationUpdateMask: 0

# 1 "\\.\DISPLAY2" Depth: 32 Primary: no
  Geometry: 960x600+1920+0 Available: 960x580+1920+0
  Virtual geometry: 2880x1080+0+0 Available: 2880x1035+0+0
  2 virtual siblings
  Physical size: 518x324 mm  Refresh: 59 Hz
  Physical DPI: 47.0734,47.037 Logical DPI: 48,48
  DevicePixelRatio: 2 Primary orientation: 2
  Orientation: 2 Native orientation: 0 OrientationUpdateMask: 0