How to simulate a retina display (HiDPI mode) in Mac OS X 10.8 Mountain Lion on a non-retina display?

Question

How can you simulate a retina display (HiDPI mode) in Mac OS X 10.8 Mountain Lion on a non-retina display?

Answer 1

I found the following instructions. It seems to work, and it is much easier than the Quartz Debug approach.

"Enable HiDPI mode in Mountain Lion w/o Quartz Debug"

https://gist.github.com/3191869

In brief, run the following commands, log out, log on, and the HiDPI resolutions are available in the display preferences:

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

(In my case the first command was enough; the second command just prints an error message.)