> It's incredibly complex designing any core but it'll be a lot simpler
> than trying to design an x86. It is a frighteningly expensive business:
> [...] Intel and AMD and the likes of Nvidia each spend around $500 million
> to design a new core. - All that before they go into production.

Applied Micro share that estimation:

"to develop a core from scratch would be a $400 million to $500 million type of investment, minimally"
http://www.sec.gov/Archives/edgar/data/711065/000119312512164604/d334600dex992.htm