Knowing Adobe,
I'm 100 % sure the feature won't be available on CS6.
So the experimental feature of Photoshop CC 2014 allows a 200 % UI zoom, which is in fact a 4x zoom.
It is unfortunate that it isn't more fine grained, as in W8.1 where you can choose a few possibilities between 100 % and 200 %, and even more above 200 %.
But it is experimental and one can hope that it will be improved (if possible not waiting another 2 years).
Anyway I think it is the same scaling as the one done on Mac Retina.
In any case, Photoshop is now officially useable on high-dpi monitors on Windows
Here is a comparison I did on my 3200x1800 Dell XPS 15:
These are full Res pictures that you can download for comparison at 100 %.
The image edited in Photoshop is shown at 100% and is 4096 x 2304.
OndreDive Full Resolution
Standard
Experimental 200%
