Funds are requested to upgrade a computer system to be shared among four faculty members, their associates and their students. The present system, based on an outdated Ridge 32 computer, is inadequate to handle the tasks of general crystallographic computing, least-squares refinements of protein structures at the atomic level, protein dynamics, energy minimization, surface adsorption, and the requirements as a host machine for an Evans and Sutherland 300 color graphics instrument. An upgrade to a Ridge 5100 computer system will increase our throughput by a factor of 10, and allow us to solve and refine the 3-D structures of macromolecules too large for our present computational capabilities. Selection of an upgraded Ridge computer is not only cost-effective, but also will permit direct transfer of all software developed over the last five years.
