Do hardware integrators usually build their own BMC, their own power supply, their own backplane, their own firmware, their own motherboards, their own switches, their own SDN, their own hypervisor, their own OS, their own rack design, their own blade / sled design, their own management API, and build it all in coordination with each other to produce a comprehensively new computing platform?

In my mind they’re much more like an SGI, Sun, IBM, DEC, or Apple type of play than merely an integrator.