I know that some info is still unknown but hypothetically given an X79 RIVE + 3930@5GHz how many would you be able to run before any bottlenecking 
Would say replacing my 670's with Titan X's be feasible or would I need to be looking at MB/CPU as well (gaming at 7860x1440) ?

Would say replacing my 670's with Titan X's be feasible or would I need to be looking at MB/CPU as well (gaming at 7860x1440) ?