Firstly, the splendid modes are absolute garbage. I have this monitor, and have found that my calibrations differ significantly from others. When calibrated correctly, it will look quite good. Use the ICC profiles posted above. After enabling those, use a website like http://www.lagom.nl/lcd-test/ to calibrate it manually, using the user/custom settings (not splendid modes). Don't use the nvidia panel, don't use windows calibration for anything other than cleartext.