A Spanish computer museum built a Cray-1 replica from 30 old Intel Mac minis, and it reaches about 1.3 teraflopsA Spanish computer museum built a Cray-1 replica from 30 old Intel Mac minis, and it reaches about 1.3 teraflops

A computer museum in Spain has built a full-size replica of the 1976 Cray-1 supercomputer, with a cluster of 30 Intel Mac minis inside.

The machine was made by Extrehard, the hardware lab of the Museo de Historia de la Computacion in Majadas de Tietar, in the province of Caceres. The museum says it took 18 months and marks 50 years of both the Cray-1 and Apple. It was first shown in a temporary exhibition at the museum from 15 February to 30 May, and was reported more widely this month by Ars Technica and then AppleInsider.

What is inside the Cray-1 replica?

The builder's own page gives the core figures:

• 30 Mac minis from 2012, with 64 processor cores between them.
• macOS Mojave, running as a Unix cluster.
• About 1.5 teraflops at its best.
• No fans: the minis stand vertically on aluminium rails and are cooled by convection.
• A three-screen terminal in a vintage style, which also runs a Raspberry Pi cluster and two Cray CX1 machines from 2006.

Ars Technica and AppleInsider say 25 of the minis have dual-core Core i5 chips and five have quad-core Core i7s. Ars says two of them are 2014 models rather than 2012. The original Cray-1 peaked at about 160 megaflops.

Where do the reports disagree?

On speed, mostly. Ars reports about 1.3 teraflops in recent tests, and the 1.5 figure from an earlier run before one node failed. AppleInsider's summary says up to 1.5 and its body says 1.3. Ars adds that the benchmark is a custom Python matrix multiplication script rather than Linpack, the test used for supercomputer rankings. AppleInsider calls the Cray machines on the console 2004 models; the builder says the Cray CX1 launched in 2006, and we follow the builder. AppleInsider also mentions crowdfunding for 70 to 80 M4 Mac minis, which the museum's pages do not.

Our take

Take the headline number loosely. Comparing a 2026 Python benchmark with the Cray-1's 1976 peak gives a ratio in the thousands, and it is fun, but it is not a like-for-like test. What the build actually shows is more modest and more interesting: computers Apple stopped supporting years ago still do real work when someone gives them a job.

That is a pattern we keep reporting. OpenCore Legacy Patcher is bringing macOS Tahoe to older Intel Macs, and ToshLLM runs open AI models on Intel Macs with AMD graphics. Each finds a use for hardware that Apple's own software has left behind. The museum chose Mojave, the last macOS to run 32-bit apps, and did not say why.

APPDOOK's reading is that the Mac mini is the right machine for this because of its shape, not its speed. A small, quiet, square box stacks neatly, and thirty of them fit inside a cabinet designed to hold a 1970s supercomputer. If the museum does move to Apple silicon minis, the same cabinet would hold far more computing power. The silence would remain the best part.