A Spanish museum rebuilt the 1976 Cray-1 supercomputer using 30 old Mac Minis, and the tribute now beats the original.
The Museo de Historia de la Computación in Spain wired together 30 Mac Minis from 2012 to 2014: five quad-core i7s and 25 dual-core i5s, 70 cores in all, running macOS Mojave and splitting tasks over MPI. In testing, the cluster hit 1.5 teraflops. The machines sit inside a replica of the Cray-1's distinctive C-shaped cabinet, cooled by rising hot air instead of fans, so the loudest thing in the room is a pair of gigabit Ethernet switches humming at about 30 decibels. A retro-styled terminal runs the show, combining a Raspberry Pi that emulates vintage environments, a Raspberry Pi cluster, Cray CX1 units running CentOS, and a Mac Mini coordinating the whole setup.
That 1.5 teraflops figure is the real punchline. The original Cray-1 topped out around 160 megaflops, meaning a pile of decade-old consumer hardware now outruns the machine that once defined supercomputing, by close to 10,000 times. It is a tidy illustration of how far commodity computing has traveled since 1976, built to mark the Cray-1's 50th anniversary.
The museum is not done showing off. It is crowdfunding 80 M4 Mac Minis to try to land a spot on the Top500 list of the world's fastest supercomputers, using the same mass-market boxes sitting under millions of office monitors. Cray would probably find that funny.