The CHM has got from IBM an intermediate assembly unit from one of IBM’s “Blue Gene”s.
Its aquisition number (or “catalog number”) is 102740911.
It holds 36 computer chips which I presume each hold one or several Power processors.
The volume for these 36 chips is 0.0195 m3.
Two of its dimensions appear to be designed for close packaging.
The 3rd dimension seems to be designed to carry a substantial cooling wind.