Extremely slow viewport

Hi,

I was testing out some of the materials in the WIP library and notices an extremely slow viewport.
Some figures:
Material with image as texture applied : Time to regen viewport 100 times = 72.50 seconds.

I unchecked Advanced Texture Preview in the rendered Display Mode:

Material with image as texture applied : Time to regen viewport 100 times = 0.64 seconds.

Is this expected, and/or is it going to be optimized. It’s not possible to work with such a slow display.

RHINO:
Work In Progress
(6.0.15132.14591, 12-May-15)
Beta

My GPU:

Thanks
-Willem

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