Casecutter Whew... that was 3 breath sentence.



But it's that last one that surprises, all of a sudden rumors say 1st Gen HBM is constrained, even though SK Hynix indicated client shipments started in January 2015. While this says SK Hynix is "ready" for HBM2, sure not near production but appears on track.



What's more in question is where is TSMC with 16 nm FinFET? As from some of the rumors others have been "investigating options" or at "keeping open mind" for their next shrink. Some speculate TSMC might not have full production for large power budget IC's until Q3 2016. Such a lapse might give AMD the window to get Arctic Islands parts solidly vetted at GloFo and still be ready by this time next year.

I get the impression it is the 2x1GB stacks that are constrained; everything points to that imho.First, and for a long time, we heard 'Fiji' was only going to be 4GB (4x1GB). Then we heard murmurs AMD was internally battling with offering an 8GB design, even though it may hold up production and raise the price over $700. Then, we got that slide deck that included what appeared to be info fresh off the line about making 2x1GB stacks (likely meaning the bandwidth of a single 1GB stack with two connected stacks or 2x chips in a stack)...something that nobody really saw coming (HBM1 was going to be 4hi 1GB, HBM2 up to 8hi 4GB). I have little doubt this was a last-second addition/decision as they noticed peoples' concerns with 4GB per gpu (especially in crossfire) for such an expensive investment. This can be noticed by the frantic 'dx12 can combine ram from multi gpus into a single pool' coming across the AMD PR bow.AMD really seems in a tough place with that. 4GB is likely (optimally) not enough for the 390x, especially with multi-gpu in the current landscape, but 8GB is likely a little too much (and expensive) for a single card (and I bet 390 non-x will be perfectly fine with 4GB aimed at 1440p)...it's the reason a 6GB similar-performance design from nvidia makes sense....that's just about the peak performance we can realistically expect from a single gpu on 28nm.One more time with gusto: 28nm will get us ~3/4 of the way to 4k/8GB making sense on the whole. 14nm will pick up the slack..the rest is just gravy (in performance or power savings).While I want 4k playability as much as anyone in demanding titles (I'm thinking a dual config on 14nm is in my future, depending on how single cards + dx12 handle the situation), I can't help but wonder if the cards built for 1440p60+ will be the big winners this go-round, as the value gap is so large. That is to say, 390 (non-x, 4GB), perhaps a cheaper gtx 980, and/or a similarly-priced salvage GM200.