GTX 980 Ti or GTX 1070?

DreamsEdits

Prominent
Feb 18, 2017
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I'm gonna buy a graphics card especially for 3D, for modeling and animating.
I've noticed that the gtx 980 ti has 2816 cuda cores while the gtx 1070 has 1920,also the gtx 980 ti has 6gb and the gtx 1070 has 8gb.

I need to know, which one is gonna perform better like in Autodesk maya viewport 2.0,i mean for the quick previews.
I usually use Maya and Zbrush.
Gaming is irrelevant.
If someone could help, i would really appreciate it :)