there is problem for viewport: firewire..maybe it's bug..i dont know..

hello

blender is 2.76 and i work 3d modelling, but i find strange wireframe… see my screenshot:
http://sendvid.com/u3mw1scx

i dont know if it’s BUG or other problem…

nothing news…it’s bug?

Does the same thing happen on other scenes?

I FIND PROBLEM!

problem: i did active "use OpenSubdiv, i disactive opensubdiv result: not show strange wireframe.

then opensubdiv is bug?