The T3D consisted of between 32 and 2048 Processing Elements (PEs), each comprising a 150 MHz DEC Alpha 21064 (EV4) microprocessor and either 16 or 64 MB of DRAM.
These switches had a peak bandwidth of 300 MB/second in each direction and were connected to form a three-dimensional torus network topology.
There was also a liquid-cooled MCN model which had an alternative interconnect wire mat allowing non-power-of-2 numbers of PEs.
The Cray T3D MC cabinet had an Apple Macintosh PowerBook laptop built into its front.
Its only purpose was to display animated Cray Research and T3D logos on its color LCD screen.