Spain Computer Museum Unveils Cray-1 Replica Built From 30 Mac Minis

The Museo de Historia de la Computación in Spain has unveiled a 1:1 scale visual replica of the Cray-1 supercomputer, powered by 30 Mac Minis, most of them from 2012, according to Ars Technica.

The museum spent 18 months developing the project. The cluster runs macOS Mojave (10.14) so it can use the operating system's built-in MPI support, and in its most recent tests it combined 64 active processing cores for 1.3 teraflops.

The museum previously reached 1.5 teraflops using all 70 available cores before one node went offline. Benchmarks were run with a custom matrix-multiplication Python script.

Of the 30 machines, 5 are quad-core i7 PCs and 25 are dual-core i5 models. The museum used passive convection cooling via a steel rack chassis and aluminum tray mounts, making the cluster nearly inaudible.

Historical context

The original Cray-1 dates from 1976 and had a peak theoretical performance of about 160 megaflops. It used vector processing, applying a single instruction to multiple data elements at once. The replica serves as a 50th-anniversary tribute to the Cray-1 and Apple's founding.