Videocardz.com: Well, maybe this is not a leak, but prediction. Hard to say, it’s quite good source though — they leaked Tahiti specs few months before launch. AMD Radeon HD 8000 series are believed to feature Sea Islands GPUs. This updated Graphics Core Next architecture would still be made with 28nm process. It’s worth saying that HD 8870 and 8850 would not be the fastest Sea Islands GPUs in the pack. The one that we are going to describe should be compared to Pitcairn, which has 2.8 billion transistors. The GPU that is powering Radeon HD 8870 and HD 8850 is called Oland and it would feature 3.4 billion transistors. Die size of this Oland processing unit is estimated at 270-280mm2.
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More heat, more power drain, less efficient, more expensive.
Nothing out there requires the horsepower anyway.
The computer that produced Avatar,
"Thirty four racks comprise the computing core, made of 32 machines each with 40,000 processors and 104 terabytes of memory."
http://www.datacenterknowle...
Dual GPU simply induces bragging rights (to those who are convinced) and headaches.
I've been building computers for 13 years now, and I've never been happy with dual gpu.
http://www.youtube.com/watc...
However if this is true source then well done AMD.
That's for producing a movie, with exactly the action they require, and building a huge world.
You would not need those specs for a game to get close.
As for open worlds, Crysis was 2007. Graphics have improved in many area's.
DX11 is really in it's infancy.
But i think 2014-15 will be interesting.