Caribbean Islands will only be out maybe middle of next year.
So, either Apple will update nMP early next year and use existing Tonga and Hawaii GPUs (Crossfire through PCIe supported), or wait another year or even more (while at it just wait for Broadwell or even Slylake with TB3 - why not?!!) and use the newer GPUs. With all the waiting maybe they'll even use the successor to CI, who knows?!
I'm confident that Apple will update soon enough, although it's strange that there is no solid info yet.
But Apple can keep it's secrets...
So, either Apple will update nMP early next year and use existing Tonga and Hawaii GPUs (Crossfire through PCIe supported), or wait another year or even more (while at it just wait for Broadwell or even Slylake with TB3 - why not?!!) and use the newer GPUs. With all the waiting maybe they'll even use the successor to CI, who knows?!
I'm confident that Apple will update soon enough, although it's strange that there is no solid info yet.
But Apple can keep it's secrets...