China is ramping up efforts to become the world's supercomputing superpower.
Its Nebulae machine at the National Super Computer Center in Shenzhen, was ranked second on the biannual Top 500 supercomputer list.
For the first time, two Chinese supercomputers appear in the list of the top 10 fastest machines.
However, the US still dominates the list with more than half the Top 500, including the world's fastest, known as Jaguar.
The Cray computer, which is owned by the Oak Ridge National Laboratory in Tennessee, has a top speed of 1.75 petaflops.
One petaflop is the equivalent of 1,000 trillion calculations per second.
It is used by scientists conducting research in astrophysics, climate science and nuclear energy.