It doesn't have any compute abilities at all though does it? Not one unit as far as i understand it. I've heard (and i don't know if this is true) that the only way around it for Nvidia is to disable the compute effects via the drivers. I heard (again i don't know if this is true) that is where the massive gains came from in Tomb Raider.(45% or whatever the figure was)
It's the double precision floating point performance that GK104 suffer in, if you compare GK104 to GK110, GK110 has over 10x the double percision performance though I do believe this is purposefully by design, as I suggested earlier it would give people even less reason to buy Tesla and Quadro cards if nVidia's desktop cards had great compute performance.
The 680 has compute abilites, just really limited. Remember Nvidia put two GK104's together and called it the K10 for the Tesla market, because they had nothing else available.
As the above, I fully think this was intentional.
The 560Ti variant of GF110 has 515 GFLOPs of double precision floating precision processing power.
The GTX580 variant of GF110 has 666 GFLOPs of double precision floating precision processing power.
Put that in to perspective, compared to the above;
The GTX680 variant of kF104 has
95 (yes, ninety five) GFLOPs of double precision floating precision processing power.
If you compare that to the DP GFLOPs of the GK110 chip, at 1310 DP GFLOPs, you can see that nVidia have intentionally designed their desktop gaming chips to excel only at games, they do have the ability to do compute tasks, but aren't very good with it.
This has firstly allowed nVidia to produce a much more cost effective GPU as they haven't have to dedicate die space for DP GFLOPs performance, and secondly, they don't canilbalise Tesla sales for those who rely on CUDA accelerated apps.
Because as I said earlier, if their desktop GPUs have great double precision/compute performance, there would be lead reasoning/justification for people to buy Tesla cards.
So I believe that they are going to continue that way with Maxwell too, and I think they will continue to do it for the foreseeable future until CUDA isn't industry standard in the sectors it's widely used in, because traditionally AMD GPUs tend to have the stronger DP GFLOPs performance, for example,
7970 at 1050Mhz on the core has 1075 DP GFLOPs
If you compare that to GK110's DP performance at 1310 DP GFLOPs, that's only 1.21x the DP GFLOPs for 1.59x more die space.
Now currently, AMD's DP GFLOP performance is quite irrelevant because not much at all is really there to take advantage of it due to the persistence of CUDA.
On another note, I would say that examining the differences in nVidia's GPU DP GFLOPs performance proves that GK104 wasn't ever intended to be the mid range GPU at all, and was clearly their high end games GPU because previous nVidia GPUs had much higher DP GFLOPs performance for the same die size.