Indeed, even the oldest, slowest Xeons shipped in SECC cartridges with integrated heatsinks.

But that was several years after the book cited by the GP was published (1994, shortly after the release of the original Pentium).

Ah I missed that on my first read, was more focused on the claim at the end of the sentence. Thanks.

The first Xeon looks to be released 1998, so sounds about right