Apparently like the price of the GTX-680 is gonna be ridiculous, my hope of seeing it at £300 ish has just evaporated.
I wouldn't get too bogged down in rumours because no one knows what any of them are called yet. "big" kepler could end up being the 680gtx and at well over 500mm2 there isn't the slightest chance in hell that thing will be under £300, likely closer to £500 on launch.
In terms of GK104 and if it ends up being called the 680gtx, it won't be £500, it won't smash a 7970, it certainly won't come close to a 7970 at 1200Mhz(which will either suddenly make an appearance as uber overclocked 7970 special editions or a new 7980 or something). £300 max for it, and don't forget, launch price, if they launch too low then AMD will drop prices quickly and they'll both.
The higher the launch price, the less AMD will drop prices to be competitive with it, basically we'll have to see where it drops.
Interesting article from Charlie and a fairly depressing sounding conference call for Nvidia.
Remember the "28nm yields suck" from a SINGLE source which every single other source, which were all directly from companies involved, said the opposite, and that was 5 days before Nvidia lowered their forecast based on lower yields than expected, and now they are again blaming low yields when no one else claims yield problems at all.
It's only guessing and adding the dots so far but theres a strong implication that Nvidia is once again having yield problems no one else is having, not entirely unexpected. Same thing happened on 40nm, you have a dozen companies making 40nm chips with not perfect yields and companies were saying yields were lower than hoped, but they were all working while Nvidia were claiming yields were in the toilet and its all TSMC's fault. Same thing seems to be happening yet this time 28nm yields by everyone else are said to be better than expected(though that is largely an expectation brought down by what happened on 40nm) and no issues at all for anyone else.
A 340mm2 core with poor yields will cost more to make than a roughly 360mm2 core with decent yields, depends entirely on how poor the yields are as to the cost difference. I'd be surprised, both because 28nm is better than 40nm at the same point and the size difference, if GK104 yields were anywhere close to as bad as gf100 yields.
But Nvidia have supposedly both scrapped their 28nm Fermi mobile shrinks as well meaning, potentially they are having bad enough yields on tiny tiny parts that it isn't worth making them either.