Here's what I use (A00 version):
Brightness: 33%
Contrast: 75%
Colour preset on monitor: Standard
ICC colour profile from TFTCentral: http://www.tftcentral.co.uk/icc_profiles/dell_s2716dg.icc
Gamma in Nvidia Control Panel: Display -> Adjust Desktop Colour Settings -> Gamma 0.8
Brightness: 33%
Contrast: 75%
Colour preset on monitor: Standard
ICC colour profile from TFTCentral: http://www.tftcentral.co.uk/icc_profiles/dell_s2716dg.icc
Gamma in Nvidia Control Panel: Display -> Adjust Desktop Colour Settings -> Gamma 0.8

So it's still A04. That's weird, it says A05 in your manual. Can you take a screenshot of where it says that?