fortunately, none of that was very convincing.
Barring massive stupidity (on the part of MS/Sony), they will use a custom part.
How is a custom part going to significantly differ from a PC part? Strip some codec stuff, side port, trim out 64FP support, etc. But what, at the end of the day, is it going to look like in regards to performance fundamentally when you are still stuck in the ~ 250mm^2 range, < 125W TDP for GPU and Memory, have to be mindful of your pad not being too large that you cannot scale down (e.g. 256bit), and are staring down 28nm at TSMC?
Serious question because you found it unconvincing, I would like to know how a custom part, in your mind, is able to work within that framework and come out far ahead.
And worth noting the post isn't about a specific part but the performance/watt and how it is scaling on processes and what ballpark that is setting. Just being a console part won't all you to get 2x the performance at a set footprint--if it were possible PC parts would be doing it. A console can get away with cutting out PC specific features that may be redundant--but what do you think that gains you?
I have been reading the TSMC white papers on 28nm and there is no miracle there. For the same # gates they are advertising a 45% performance increase w/ the same leakage when moving for 40G to 28HP. Once you add more shaders, TMUs, etc you are either going to increase leakage or have to scale back performance to stay in the same TDP. Which, if as I mentioned, includes scaling up the shader arrays, TMUs, etc means you are effectively at a ceiling.
For a set TDP have to pick 2 of the following (within reason): Large Area, Fast Frequency, Power Efficient.
You can have Large and Fast ... at the expense of being power hungry and expensive so mark this one off.
So your real options are:
You can have Large and Efficient ... at the expense of having lower clocks.
You can have Fast and Efficient ... at the expense of not being very large.
I know AlStrong gets pissy every time I mention 4GB of memory or 3GFLOPs (booh hiss! Al, they could do it if they wanted to--and should) but I do concede to Al there is no magic panacea console special sauce coming from AMD or NV that will blow away the current GPUs.
Actually, because of how AMD and NV have attacked the PC market differently AMD is currently making PC GPUs *very similar* to the constraints set forth for a console GPU. Barts looks like a GPU that could fit into a console if it had shipped in 2010.