30 Mac Minis Power 1:1 Replica of 1976 Cray-1 Supercomputer

The Museo de Historia de la Computación in Spain has unveiled a 1:1 scale visual replica of the 1976 Cray-1 supercomputer, powered instead by 30 Mac Minis rather than expensive, cutting-edge tech, Ars Technica reported.

Building a 1976 Supercomputer Out of 30 Obsolete Mac Minis

Spanning an 18-month development cycle, the project serves as a dual tribute to the 50th anniversary of the Cray-1 and the founding of Apple. Integrating hardware from over a decade ago into a unified computing cluster presented distinct engineering hurdles. The array consists of 25 dual-core i5 models and five quad-core i7 units. With the exception of two machines manufactured in 2014, the hardware dates back to 2012.

When networked together, the 64 active processing cores deliver a combined 1.3 teraflops of performance during recent tests. Prior to a single node dropping offline, the museum’s peak configuration achieved 1.5 teraflops utilizing all 70 available cores. Benchmarks were gathered by running a custom matrix-multiplication Python script.

Vector Processing Versus Parallel Cluster Architecture

Visitors to the museum can observe the system executing matrix algorithms in real time. The demonstration maps performance scaling from a single core up to the full array operating in parallel.

Architecturally, the project contrasts sharply with the machine that inspired it. The original Cray-1 relied on vector processing, executing a single instruction across multiple data elements simultaneously. By contrast, the Mac Mini replica distributes workloads across independent processors within a parallel cluster. While the peak theoretical performance of the original 1976 Cray-1 reached roughly 160 megaflops, consumer hardware from decades later vastly surpasses those metrics.

Configuring macOS Mojave for Message Passing Interface

Rather than deploying a standard Linux distribution, the development team selected macOS Mojave version 10.14 to manage the hardware. The operating system provided native support for the Message Passing Interface, the software layer enabling individual nodes to communicate and distribute tasks across the cluster.

Cooling a multi-node setup without generating excessive noise required a deliberate hardware layout. Instead of relying on conventional data center fans, the engineering team implemented passive convection cooling through a steel rack chassis and aluminum tray mounts for each Mac Mini, keeping the installation nearly inaudible.