Earth Simulator
The K computer's placement on the top spot was seven years after Japan held the title in 2004. NEC's Earth Simulator supercomputer built by NEC at the Japan Agency for Marine-Earth Science and Technology (JAMSTEC) was the fastest in the world at that time. It used 5,120 NEC SX-6i processors, generating a performance of 28,293,540 MIPS (million instructions per second). It also had a peak performance of 131 TFLOPS (131 trillion floating-point operations per second), using proprietary vector processing chips.