i'm not following, what do you mean by the only way to get from 30 to 60 fps is by having a twice as powerful CPU?

so let's say (to simplify the argument) that I'm playing battlefield 4 on PC with processor X and a GTX 670 getting about 60 fps on average in high quality.

if i want to double the fps count to 120 i should:

a) get processor Y with double the frequency of processor X, but keep the same gfx card

b) get a gtx 970 and keep the same processor X

Which one of these scenarios do you think will double your FPS?

edit: just to help out, here's a reference benchmark for the same gfx card testing the fps output with different CPUs

http://www.anandtech.com/bench/CPU/1291

Thats why in the example i gave i said "if you are maxing out the cpu ome the base ps4"

Look at it this way. you have gpu tasks and u have cpu tasks  to get a game running at 60fps both of them.have to finish their work load in 16ms per frame. 

If you have a CPU that can finish that in 4ms but a gpu that does it in 16ms, you are still gonna hit that 60fps target. In this csse upgrading your gpu will be able to increase your overall framerate csuse the CPU was strong enough to begin with to handle higher framerates. 

Int he case of the PS4, ehere both CPUs are pretty much identical between the base and neo based on rumors. If a game is maxing out the cpu already on the base mode and running at 30fpsl, to be able to double it on the neo the neo would need to do all the cpu work the base model does but in half the time. Get it now?

It doesnt matter how powerful your GPU is, if the CPU is a bottle neck then your framerate will still suffer. And vice versa. 

It is possible to a point.
The reason why we don't do all our processing on a GPU is because GPU's are really bad at working on single large and complex tasks, they are best when working on thousands of small tasks.

CPU's though aren't as good as a GPU when it comes to thousands of small tasks, which is why both are seperate, but they do excel at big complex tasks.

With that said, CPU's have typically been doing some of those "small tasks" like Physics calculations, which can be moved over to the GPU, the Playstation 4 was already doing this, so whether such a thing can continue is another matter entirely.

As systems are today, you would be right.
But there is still the possible potential for a 512bit bus for System Ram to feed an APU, just no one has done it because of costs, the amount of traces required to support a 512bit bus results in increased PCB layers and thus complexity, which is one of the issues HBM solved by using an interposer.

With that said, AMD is working on a large and power hungry APU for the HPC market, which is likely to be using HBM on a 1024 or higher bit bus.

Very possible, but that will depend on the dev and what tasks they will offload to the GPU, not everything can be offloaded to the GPU though due to architectural and fundamental chip design differences. (Serial vs Parallel processors.)

I would think most developers would use the extra horse power to close the graphics gap between console and PC though as it shouldn't really cost them any extra development time as the work was already done for PC.

And absolutely no talk about the Scorpio splitting the userbase even though it's said to be able to run Oculus. Amazing.

what userbase? :D

(just kidding, don't throw stones please) lol

But it's true though isn't it. There were many articles about how the Neo could (or would) split the PS4 userbase and many comments in Neo threads saying the same, and yet here we are with the Scorpio (a year from release according to rumours) and no mention of splitting the userbase. BUT, if the rumours are true and it can run Oculus, that means only Scorpio owners will be able to play Oculus and those with the vanilla version won't be able to, which splits the userbase. This is yet another example of a narrative being pushed that fits better with one console but for some reason it's only being used for the PS4.

PS4neo will probably be close to scorpio in features and capabilities.

2306*2*0.911 = 4.2 Tflops. (PS4 neo)
2306*2*1.2 = 5.5 Tflops. (normal RX 480 for pc) (which could be what the scorpio has)

^ this is most likely the differnce.

But it's true though isn't it. There were many articles about how the Neo could (or would) split the PS4 userbase and many comments in Neo threads saying the same, and yet here we are with the Scorpio (a year from release according to rumours) and no mention of splitting the userbase. BUT, if the rumours are true and it can run Oculus, that means only Scorpio owners will be able to play Oculus and those with the vanilla version won't be able to, which splits the userbase. This is yet another example of a narrative being pushed that fits better with one console but for some reason it's only being used for the PS4.

Yes, that's true, plus there has been no indication at all that this new Xbox would be sharing the game library with the Xbox 1, so I tend to think it would actually be a new 'generation' and MS throwing in the towel earlier.

If the supposed 5.5 TFLOPs performance is true then it means they are done with esram completely (good for them, about time) which would mean a complete change in architecture.

The reason why not many seem to care is because afterall only 20M were sold so far and the initial vision has changed so much (mandatory kinect, always online drm, cloud computing processing graphics for games lol,etc) that pretty much everyone is quite jaded by now.

MS was caught with the pants down screwing the maid this generation and no matter what they would do it would still look stupid, probably they realized it's time to reset and get a fresh start. Too little too late? perhaps