An upgrade is transforming Oak Ridge National Laboratory's Jaguar supercomputer, America's fastest, into Titan, a next-generation supercomputer that will employ the latest AMD Opteron central processing units as well as NVIDIA Tesla graphics processing units ? energy-efficient processors that accelerate specific types of calculations in scientific application codes. Titan's hybrid architecture will bring fundamental changes for researchers from academia, industry and government that employ computing resources. Members of the Oak Ridge Leadership Computing Facility's Application Performance Tools group are collaborating with Allinea, CAPS Enterprise, and the Technical University of Dresden to develop software tools to help with new challenges presented by Titan's design. —Eric Gedenk