I worked at a small start-up producing COM-HPC boards for companies who wanted to keep their servers in-house, as opposed to using cloud infrastructure. We weren't purchasing any more than maybe 500 CPUs of their upcoming platform. Despite that, they supplied 1:1 tech support, reference schematics/layouts, a reference validation platform with which to test our design on, and 1000's of documents including product design guides and white papers. This all came about by just contacting Intel's developer account support and filling in a few forms.
We also produced the same product with AMD hardware and the difference was night an day. Say what you will about their production difficulties and roadmaps, their engineering support is years ahead of AMD.