HiDPI on Mac OS X EL Capitan, Dell U3011

Overview

El Capitan:

Turn off System Integrity Protection so we can copy file to /System

• Reboot your Mac into Recovery Mode by restarting your computer and holding down Command+R until the Apple logo appears on your screen.
• Click Utilities > Terminal.
• In the Terminal window, type in csrutil disable and press Enter.
• Restart your Mac.

Step 1:

sudo defaults write /Library/Preferences/com.apple.windowserver DisplayResolutionEnabled -bool YES;
sudo defaults delete /Library/Preferences/com.apple.windowserver DisplayResolutionDisabled;

Step 2:

Create an override file for your display. You may use my script to do that.

sudo ruby hidpi_osx.rb

Step 3:

Reboot, HiDPI mode is available.

Reference

• http://www.tonymacx86.com/graphics/102321-guide-add-your-custom-retina-hidpi-resolution-your-desktop-display.html
• https://github.com/chengguangnan/hidpi_osx