Sipearl has successfully powered on Rhea1, the first processor developed under the European Processor Initiative and what the company calls the most complex server CPU ever designed in Europe. The French chip design house announced that the first silicon came to life on 13 May and is now undergoing a 12-week bring-up and validation process. Initial results are said to match expectations, paving the way for general availability by the end of 2026. Rhea1 is a key building block in Europe’s ambition to establish a sovereign HPC and AI computing stack.
The processor integrates 80 Arm Neoverse V1 cores, 64 GB of HBM2e memory in four stacks, four DDR5 memory interfaces and 104 PCIe Gen5 lanes. With more than 61 billion transistors, Rhea1 targets supercomputing, AI inference and data-intensive workloads while emphasizing energy efficiency and what Sipearl describes as back-door-free and kill-switch-free security.
Rhea1’s first customer will be the Jülich Supercomputing Center in Germany, where more than 2,600 processors will be installed in over 1,300 nodes of the Jupiter supercomputer. The CPU cluster contributes roughly 5 petaflops to the machine’s overall performance, which exceeds one exaflop, making Jupiter Europe’s first exascale system. Sipearl says Rhea1 fulfils the mission assigned by the EU to bring advanced processor expertise back to Europe.
The milestone also highlights the challenges of rebuilding a European high-performance processor industry. Originally scheduled for release in 2021, Rhea1 will reach the market five years late. As a result, some of its technology choices, including HBM2e memory and a manufacturing process derived from the 7-nanometer generation, lag behind the latest offerings from AMD, Nvidia and other competitors.
Sipearl is already developing a successor, Rhea2, which is expected to power France’s future Alice Recoque exascale supercomputer and narrow the technology gap.
