How are plants and tress from the Linden Library different from other prims?

[Zippy Sands]

I just upgraded the video driver of my ATI Radeon HD 5800.  Under viewer  2.7.1 (232828) all seems fine except for items rezzed from the Linden Library of plants and trees, they all switch rapidly from a properly rezzed texture to a pixelated texture.  New driver works fine with all other prims and textures.  New driver also works fine with third party viewer.  If I roll the driver back all is well again.  What is different about these prims that they fail to rezz properly?

[LoveAngeL Lyre]

Hello Zippy. Linden trees are the system-provided foliage that is listed in your Inventory's Library > Objects > Trees, plants and grasses folder. They have a number of tricky caveats to them, such as not being highlighted when selected. They also can't be linked to objects, making them even tougher to transport, although they can be included in a coalesced object. These trees are special pre-modelled object types created (possibly in Maya) by Lindens outside of SL. They react to wind, emulating a windblown effect, and will often go through other objects since no collision detection is performed on the tree. Not sure why you can't rezz them properly under viewer 2.7.1., although they look fine with the TPV's and if you roll the driver back. Try to clear your cache and see if that helps.  

[Zippy Sands]

Actually I tried clearing the cache and even deleted the cache physically to avoid corruoted textures. I know the texture is fine because I placed it on a noc prim with a script and it renders correctly. There is some property of these prims that thw video driver must not be handling properly. Thanks for your ideas.