Top500: In the T500’s latest assessment of computer speed, China’s Tianhe-2 supercomputer came out on top. Located at China’s National University of Defense Technology in Guangzhuo, Tianhe-2 whizzed through a benchmark calculation at a rate of 33.86 petaflop/s (1 flop corresponds to a single computational operation on a number, such as 6.37 × 103, that has an exponent). Tianhe-2’s nearest rival, Oak Ridge National Laboratory’s Titan, used to hold the record at 17.59 petaflop/s but lost it to Tianhe-2 in the previous T500 assessment, which took place in June. The T500 assessment does not take into account how quickly a computer moves data within itself in order to carry out a real-world calculation, a limitation that has led some in the supercomputer community to advocate a new benchmark test. All four of the world’s fastest supercomputers require an order of 10 megawatts of electrical power to operate.