Late last year we reported that AMD had cut ties with TSMC and would be manufacturing their GPU and APU products at Global Foundries. NVIDIA still uses TSMC to manufacture their chips, but recently they have moved to Samsung for 14 nm production. TSMC has just announced that they will not make any 20 nm GPUs at all, if anything 20 nm comes out of TSMC it will be low power ASICs.
High performance discrete GPUs will never make it to 20 nm. This is because the process has too many power leaks and and poor yields with big cores. Because of this the GPU industry will move to 16 nm FinFET with TSMC in 2016 or even 14 nm with Samsung and Global Foundries.
To get 16 nm off the ground TSMC has invested $500 billion Taiwanese dollars in an advanced chip factory. This translates into about $16 billion USD. While $16 billion sounds like a lot, Intel invested more than $6 billion in Israel based fabs since 2006. Intel is only now preparing Israel fabs for 10 nm, while their 14 nm products are being manufactured in Ireland. It has been said that each transition cost to a new node grows exponentially each time.