something wrong there, a 980 should do x3 750ti, maybe not optimized code for maxwell 2.0, notice nits5 at 99%, that's x3 750ti, the other are not well optimized for sure
maybe the 980 is at default , not oc'd
so 140w for 6.6M on x11 vs 2.5 750ti to obtain that, but you need 150w , also for every 1 rig with 980(at full tdp usage) you need 3 750ti, they are better just for this, but the price is a big no no for now
It's probably just stock or even reference
This makes me doubt even more if I'd want a 9xx. If the 970 is in the same line, and no one is able to optimize X11 (and others) for maxwell 2.0, a 750TI is still the better choice for mining. And as I said before, my 760 is still doing fine enough for my taste, no need for a new card just for gaming.
Anyways, a 970 would still be the best bang for the buck for gaming, if you need more power, just sli two. 980 just isn't 'it'.