If your video card(s) have the capability, you might try setting the preview render settings (not the Firefly settings) tab to preview in OpenGL with hardware acceleration. 

Preview in SreeD, no hardware acceleration:

 

Notice how tiled materials are not tiled in the preview, just one big instance of the texture image is applied.  No attempt to show procedurals, either.

Now, set the preview render settings.  If your card is capable of hardware acceleration, Poser will tell you by displaying the (hard to see) notice in green text.  Here are the preview tabs for two different computers with different video processors.

And this is the same preview, but in OpenGL with hardware acceleration:

...

Poser 12, in feet.  

OSes:  Win7Prox64, Win7Ultx64

Silo Pro 2.5.6 64bit, Vue Infinite 2014.7, Genetica 4.0 Studio, UV Mapper Pro, UV Layout Pro, PhotoImpact X3, GIF Animator 5