The US still holds the crown for fastest supercomputer, but it's now a Cray XK7 system known as Titan that has overtaken the previous titleholder, the IBM Sequoia. US and German researchers found that Titan, funded by the Department of Energy and housed at the US government's Oak Ridge National Laboratory in Tennessee, can reach 17.59 petaflops (quadrillions of calculations per second), AFP reports. IBM Sequoia is in second place now, at 16.32 petaflops.
The rest of the top five included computers in Japan, Chicago, and Germany. Of the top 500, 251 are in the US, 123 in Asia, and 105 in Europe. Titan is used for scientific research on topics including energy, climate change, and efficient engines. (Read more supercomputer stories.)