The following image shows you the finished board housing with its key components as well as some installed BBBs. Here, a indicates the threaded rod with the straw as the spacer, b indicates BeagleBone Black, c indicates the Ethernet cable, d indicates 3.5" hard disc cooling fans, e indicates the 5 V power cable, and f indicates the plate with drilled holes.

The finished casing with installed BBBs

One of the most important things that you have to consider before building a super computer is the space you require. It is not only important to provide stable and practical housing for some BBB boards, but also to keep in mind that you might want to upgrade the system to more boards in the future. This means that you require a scalable system that is easy to upgrade. Also, you need to keep in mind that every single board requires its own power and has to be accessible by hand (reset, boot-selection, and the power button as well as the memory card, and so...