DescriptionGlobal Scientific Information and Computing center (GSIC) at Tokyo Institute of Technology has started the operation of the brand-new supercomputer, called TSUBAME3.0 in August 2017. The proposition submitted by SGI Japan has been adopted in January; since then, GSIC, SGI Japan and related vendors have cooperatively promoted preparations towards the operation start. The target applications area of TSUBAME3.0 is not limited to typical HPC area, but includes big-data and artificial intelligence (AI) area. The main components of the system are 540 compute nodes, which are customized version of SGI ICE XA. The total numbers of CPUs and GPUs are 1,080 and 2,160, respectively. The total performance is 12.15PFlops in double precision and 47.2PFlops in half precision (or more), which is an expression of floating point values in 16bit, which is expected to be useful in big-data and AI area. TSUBAME3.0 has excellent power efficiency, largely owing to GPU accelerators of the latest generation. The power-performance ratio, 14.11 GFlops, won world No.1 in the Green500 List in June 2017.