According to a recent report Apple may possibly contract AMD to design a semi-custom x86 SoC for its iMac products in 2017 and 2018. This deal would allow Apple to secure a high performance x86 SoC design at a significantly lower cost than competing Intel solutions.
In the timeframe of 2017 – 2018 AMD should have two high performance CPU cores. One would be an ARM design codenamed K12 and the second one is of course Zen. This would actually be the second generation of Zen, or “Zen+” x86 design. It is likely that Apple would use the Zen SoC design.
Even if they are offering a much lower cost than Intel the contract would be huge, much like what AMD did with the console market. Not only that it would be great press and boost viability for the company’s semi-custom business.
Apple and AMD already have a good relationship as AMD provides the graphics chips for current iMac and Mac Pro products.