Forschungszentrum Jülich celebrates Europe's first Exaflops Supercomputer

Goal achieved: The Jupiter Booster supercomputer at Forschungszentrum Jülich has now reached its planned computing power of 1 trillion FP64 floating-point operations per second. This makes it and remains the fastest European computer.

It also maintained its 4th rank on the 66th edition of the Top500 list of supercomputers. It was published at the International Conference for High Performance Computing, Networking, Storage and Analysis (SC'25) in St. Louis.

Jupiter Booster debuted on the 65th Top500 list in June with 0.793 Exaflops/s (EFlops). Since then, experts in Jülich have put further modules into operation and optimized the system. With 63.3 billion flops per watt of power consumed (63.3 GFlops/W), energy efficiency also increased by 4.5 percent.

Some other of the top ten supercomputers on the latest Top500 list have also been optimized. However, the top 14 positions on the ranking list are occupied by the same systems as in June. Only further down are there some minor shifts and also several new entries, but in the performance range below 140 Petaflops/s (0.14 EFlops).

In addition, there is a new leader on the Green500 list of the most efficient supercomputers, KAIROS at the University of Toulouse. Like Jupiter Booster, it is a Bull Sequana XH3000 machine from the French manufacturer Eviden (formerly Atos), but with a fraction of the performance (3.046 PFlops, Top500 rank 422). However, it operates with 73.28 GFlops/W, making it almost 16 percent more efficient.

1 Exaflops more Top500 performance

The 66th Top500 list features 45 new supercomputers, including 12 from the USA, 7 from Japan, 6 from Canada, and three in Germany. The most powerful has a performance of 135.4 PFlops, the weakest 2.91 PFlops. Together, they increase the aggregated computing power of the current Top500 list by almost exactly 1 EFlops. This means the performance increase of the 66th Top500 list is relatively weak.

Half of the top ten supercomputers on the 66th Top500 list are located in Europe: two in Italy and one each in Germany, Switzerland, and Finland. However, the USA has the absolute most supercomputer computing power. China, on the other hand, has not participated in the Top500 competition for several years.

Even in light of the enormous growth of AI data centers, the significance of the Top500 list is gradually fading. However, AI behemoths are optimized for different algorithms than most Top500 systems, specifically for AI. They mostly compute with more compact number formats optimized for AI, for example, with TF32 or bFloat16 values during training, and with single-digit bit integer formats during inference. The AI computing performance figures are therefore not comparable to those from the Top500 list.

The Top500 list exclusively considers the results of the High Performance LINPACK benchmark when processing "double precision" floating-point numbers (Dual Precision/DP, FP64). 128 Top500 systems additionally ran the High Performance Conjugate Gradients (HPCG) benchmark for other scientific tasks. Many of the newer Top500 systems are also designed for the use of AI software.

66. Top500 List of Supercomputers (November 2025): Top 10
Rank	Name	Country	CPU Type	Accelerator	RMax*	Efficiency
1	El Capitan	USA	MI300A	AMD MI300A	1809 PFlops	60.9 GFlops/W
2	Frontier	USA	Epyc	AMD MI250X	1353 PFlops	55.0 GFlops/W
3	Aurora	USA	Xeon	Xeon GPU Max	1012 PFlops	26.2 GFlops/W
4	Jupiter Booster	Germany	GH200	Nvidia GH200	1000 PFlops	63.3 GFlops/W
5	Eagle (MS Azure)	USA	Xeon	Nvidia H100	561 PFlops	n.a.
6	Eni HPC6	Italy	Epyc	AMD Instinct MI	478 PFlops	56.5 GFlops/W
7	Fugaku	Japan	A64FX	–	442 PFlops	14.8 GFlops/W
8	Alps	Switzerland	GH200	Nvidia GH200	435 PFlops	61.1 GFlops/W
9	LUMI	Finland	Epyc	Instinct MI 250X	380 PFlops	53.4 GFlops/W
10	Leonardo	Italy	Xeon	Nvidia A100	241 PFlops	32.2 GFlops/W
*RMax is the floating-point performance (FP64) measured by Linpack

(ciw)