You guys do realize that 90% of all people mining ZEC are using AMD cards.
Even if the new version is 10x as fast, the hashrate will go up 9x anyways and there won't be much profit anyways.
Our competition is Nvidia GPUs and CPU botnets however I am sure the total hashrate of all those devices with ZEC is less than 10%.
Most Nvidia's went back to ETH mining and most botnets went back to XMR.
We are all on "borrowed time" pretty much when it comes to mining. Our only catch at success is to sell ZEC, buy BTC and keep it and hope SEC approves the ETF and bitcoin goes to $10,000/coin.
I'd guess closer to 80% but definitely a large majority are AMD - and quite a bit of it is likely 2GB cards that CAN"T do ETH any more.
NVidia has NOT moved to ETH - 1070s in particular are better off on ZEC than ETH and have been since the Nicehash NVidia miner got up to speed.
There HAS been some NVidia move elsewhere though - stuff like LBRY that NVidia dominates and AMD is a non-factor.