Right, that's just the Itanium machines. I'm not current on HP buzzwords.

The HP NonStop systems, Xeon versions, are here.[1] The not-very-informative white paper is here.[2] Not much about how they do it. Especially since they talk about running "modern" software, like Java and Apache.

[1] https://www.hpe.com/us/en/compute/nonstop-servers.html

[2] https://www.hpe.com/psnow/doc/4aa6-5326enw?jumpid=in_pdfview...