The Jaguar is a change of pace. While the last three systems have been newcomers to the TOP500 list, the Jaguar is an old veteran: It's been on the list since the second half of 2009! That's practically ancient in the supercomputer world, but the Jaguar, located in Oak Ridge, Tennessee, is a powerhouse. It was the fastest supercomputer in the world on the November 2009 and June 2010 lists. It spent the next year and a half at second and third place before sliding down to sixth.
Jaguar is one of the rare few computers in the top 10 to run on AMD processors, and it also utilizes a special version of Linux, the Cray Linux Environment, built for supercomputers. Supercomputer manufacturer Cray built the Jaguar for $104 million and upgraded it in 2012 to keep it competitive [source: knoxnews]. The company increased Jaguar's processor count from about 225,000 to nearly 300,000, bringing its processing power from about 2.3 to 2.6 petaflops.