well guys, there is so much said about the new ACX 2.0 cooler that I decided to look into detail.
I just took a picture of my GTX 760 ACX 1.0 and compared to the ACX 2.0 from bit-tech's GTX 970 review.
 
here are the pics for you:
 
- EVGA GTX 760 SC 4GB ACX 1.0:
 

 
- EVGA GTX 970 SC ACX 2.0:
 

 
so can someone see any difference except the heat pipes being nickel covered on the GTX 970?
even the strange cut on the third heat pipe end is the same.
 
so what does the pictures tell me? ACX 2.0 = ACX 1.0 + new fans, that's it!
there is no single change on the cooler itself, at least regarding the GTX 970 series.
 
this means EVGA is in a very good position from cost side of view against the competitors who designed a completely new cooling solution for this series.
going further I would have expected that EVGA could offer even a slightly lower prices than the competitor to share it's advantage with us, the customers.
 
would this be so wrong?

EVGA GeForce GTX 980/970 ACX 2.0
The World's Most Efficient Air Cooler
Most graphics card manufacturers only focus on one aspect when designing their cooling solution and neglect all other aspects of the fan design and heatsink. With EVGA ACX 2.0, we focused on the details that make a real difference, not just marketing jargon.
 
In fact, did you know that the power consumption of a fan can directly affect your overclocking ability? Modern NVIDIA graphics cards have a maximum power ceiling that takes into account the fan power consumption, meaning the lower the power consumption from the fan, the more power available for the GPU! Triple fan coolers from competitors increase power consumption, thereby lowering your maximum overclocking headroom. When it comes to graphics cards cooling, less is more!

 

 
Back to basics for improved efficiency.
We did a full redesign on the motor, from improved magnets, to changing how the internals are designed to help reduce acoustic noise from the fan. Furthermore we also increased the fan blade count, which creates higher pressure allowing the heatsink and fan to cool better without needing to increase the motor speed and increase noise levels. This will help reduce the temperatures of the card and keep the fan noise down, increasing the lifespan of the card; all of this frees up additional power for overclocking.
 
Fan Blade Quality
11 fan blades increase CFM and static pressure
Swept Fan Design to Reduce Fan Noise Level
Low Profile
Fan Motor Quality
Improved magnets allow for 150RPM max increase
3 Phase / 6 Slot Design Improves Efficiency
Increased Silicon Steel increases magnet strength
What this means to you
26% Lower GPU Temperature*
36% Quieter*
250% Lower Fan Power Consumption*
400% Longer Lifespan**
 
 
 

I would say the Fan Shroud and the Fan are the only changes.  No one cares about the nickel on the heat pipes, as it adds only aesthetics.  
 
OH, and they changed the TIM from the disgusting brown color to a nice gray... LOL!
 

the brown is really disgusting, isn't it?! I'm so glad I got rid of it.
 
by the way on almost all review pictures of the GTX 970 I saw too much TIM applied.

I, honestly, would much rather see extra instead of what happened with yours.
 
I am glad you tried that before sending it back, because no one would have said anything at all.

Scarlet-Tech
I would say the Fan Shroud and the Fan are the only changes.  No one cares about the nickel on the heat pipes, as it adds only aesthetics.  
OH, and they changed the TIM from the disgusting brown color to a nice gray... LOL!

The nice Gray TIM looks like it spreads better then the Brown TIM.
I  might well be a better TIM that is being used now.
 
The cover is also different at least from what I see, Air Flow has changed.