For only the second time in 24 years, the US has been edged out of the top flight of the world's most powerful number-crunchers. An upgrade to a Swiss supercomputer has bumped the US Department of Energy's Cray XK7 to number four on the list rating these machines. The only other time the US fell out of the top three was in 1996. Chinese supercomputers currently occupy the top two slots in the respected Top 500 list. Read more