The Oak Ridge National Laboratory Leadership Computing Facility (LCF) provides one of the world's most powerful computing resources for open scientific research (see the TOP500 list).  In May 2008, the Oak Ridge LCF reached 250 teraflops with the replacement of all of the dual-core processors in the Cray XT-4 system with AMD quad-core processors.  This upgrade more than doubles the performance of the system known as Jaguar.  It now has a total of 7,832 XT4 compute nodes (more than 31,000 processing cores) that deliver up to 263 trillion calculations a second (or 263 teraflops).  Each compute node contains a quad-core 2.1 GHz AMD Opteron processor and 8GB of memory.  Approximately 600 Terabytes are available in the scratch file systems.

The Oak Ridge LCF is a major computing resource for the Innovative and Novel Computational Impact on Theory and Experiment (INCITE) program.  In 2008, ASCR, part of the Office of Science at the Department of Energy, awarded more than 140 million processor hours on Jaguar to 30 INCITE projects from universities, private industry, and government research laboratories.  Such unpre-cedented levels of computational power are key to cracking fundamental questions that underlie issues of vital importance such as designing fusion reactors that provide clean, virtually unlimited energy; engineering proteins to provide new therapies for diseases and release energy from biomass efficiently; making wise choices to protect our planet and avoid runaway climate change; and designing new materials with specialized properties.  Past projects have ranged from efforts to better understand core collapse of supernovae to improving the efficiency of catalytic processes directly involved in the synthesis of 20 percent of all