https://blog.wongcw.com/2019/04/03/%e8%bf%8e%e6%88%b0amd-7nm-64%e6%a0%b8epyc%ef%bc%8c%e8%8b%b1%e7%89%b9%e7%88%be%e8%87%b3%e5%bc%b7%e4%b9%9f%e7%8e%a9%e8%b5%b7%e4%ba%86%e8%86%a0%e6%b0%b4%e4%bb%a5%e5%8f%8a%e6%80%a7%e5%83%b9%e6%af%94/