i still don't understand the ppl who think that Vega will be like 600-700$ GPU, it simply won't, because more important than performance is market segment, AMD cannot go from 229$ product to 699$ product, and lose on volume segments...
AMD Will have a 300-350$ Vega and a 450-500$ Vega, this is not prediction, this is a must for AMD, and they are not stupid enough to bypass that.
once that is done, they can find some extra value to add to bring the premium margins up, so the HBM2 and interposer cost have been factured in long before this, and the Vega Sku that sits in each segment it would have the regular 30ish% margins AMD often opte for.