The UK’s fastest supercomputer, Isambard-AI, has come online.

Housed at the University of Bristol’s National Composites Centre (NCC), Isambard-AI ranked 128 on the most recent edition of the Top500 list.

The £225 million ($273m) machine has also placed second on the Green500, a list that ranks supercomputers in terms of energy efficiency, with a rating of 68.8 gigaflops per watt.

Isambard-AI – Christy Nunn

Built on an HPE Cray EX-based system, at full capacity Isambard-AI will contain 5,448 Nvidia GH200 superchips and offer 200 petaflops Linpack and 21 exaflops of AI compute.

Currently in phase one, at present the machine offers 7.4 petaflops Linpack and 647 petaflops of AI compute across 168 GPUs. The remaining 5,280 Nvidia GH200 superchips are due to arrive at the NCC later this summer to bring Isambard-AI to full capacity.

The system also incorporates HPE Slingshot 11 interconnect, nearly 25 petabytes of storage using the Cray Clusterstor E1000, and is hosted in a self-cooled, self-contained data center using the HPE Performance Optimized Data Center (POD). A heat reuse system will direct waste head to nearby buildings.

“With the launch of the first stage of University of Bristol’s supercomputer Isambard-AI, we're witnessing a groundbreaking moment for UK science, innovation, and technology,” said Minister for AI, Jonathan Berry. “This world-class equipment will revolutionize research possibilities here in the UK, with our world-first AI Safety Institute among the organizations who are set to benefit by harnessing one of the most powerful computer systems on the planet to drive forward their vital research.

He added: “Not only does Isambard-AI rank among the world's fastest supercomputers, but it also sets the standard for eco-conscious computing, leading the charge in efficiency and sustainability. From AI safety to healthcare and climate research, its capabilities are unparalleled, marking the UK out as a global leader in AI and responsible innovation.”

Isambard-AI will eventually connect with the Dawn supercomputer cluster at the University of Cambridge. That system, which is the result of a two-year collaboration between Dell and Intel, became operational in February. While still also in phase one, Dawn currently offers 19 petaflops of FP64 performance.