They already do have; see Intel's implementation on Ivy Bridge : https://www.electronicdesign.com/resources/article/21796238/understanding-intels-ivy-bridge-ran

They already do have; see Intel's implementation on Ivy Bridge : https://www.electronicdesign.com/resources/article/21796238/understanding-intels-ivy-bridge-random-number-generator https://www.electronicdesign.com/resources/article/21796238/... (See https://news.ycombinator.com/item?id=2947936 https://news.ycombinator.com/item?id=2947936 from 2011 but the original article link seems to have gone)