Funding is requested to purchase a multi-processor computer based on the RISC architecture to replace the Convex C220. The projects for which the requested equipment will be used include: Computer Simulations of Solvated Proteins and Liquids (R.M. Levy), Computer Simulations of Double Helical DNA (W.K. Olson), Biomolecular Structure and Interactions (H. M. Berman), Potential Surfaces for Internal Rotation in Conjugated Molecules (L. Goodman), Medium Effects in Electronic Structure Calculations (K. Krogh-Jespersen), NMR Structure Determination and Protein Folding (J. Baum), and Structure and Interactions of Macromolecular Complexes (M. Georgiadis). The need for the RISC based multi-processor is based on the computationally intensive nature of these projects, and the need for the visualization of the computed results concerning complex biomolecular systems. Rutgers University is internationally recognized for the strength of its research program in Biophysical Chemistry. A central theme connecting the investigators participating in this proposal is that of "Biomolecular Structure and Dynamics". The complexity and sheer size of biological macromolecules makes the analysis of the structural and dynamic features in these systems computationally intensive. This is true for the theoretical studies including molecular modeling using computer graphics, computer simulations of biomolecules in solution and quantum chemical calculations of electronic properties of biomolecules and conjugated molecules. This is also true of the experimental techniques that are represented in the proposal: macromolecular x-ray crystallography and NMR spectroscopy. The individual projects carried out by the coinvestigators all involve very large scale computations. The shared computational facilities for molecular biophysics and computational chemistry are housed primarily within the chemistry department. The backbone of the computational resources for biophysical chemistry is the Convex C220 dual processor. In 1986 a Convex Cl uniprocessor was purchased with funding from a National Institutes of Health Shared Instrumentation Grant. In 1989, with funding provided by an instrumentation grant from the National Science Foundation and by Rutgers University, the Convex was upgraded to a dual processor C220. At the time of its purchase, the vector architecture of the Convex was quite remarkable, providing 10-50 times the performance gains over the DEC VAX 780 hardware which it replaced. In the context of today's computing environment, with the availability of RISC computer workstations, the performance of the Convex is much less impressive. At present, perhaps the only remaining remarkable attributes of the Convex are its sheer physical size, its power requirements, and exhorbitant maintenance costs. We propose to replace the Convex C220 with a multi-processor RISC computer system. A final choice of vendor will be made after competitive evaluations of alternative RISC systems is carried out after the grant award. Possible vendors include Silicon Graphics, Hewlett Packard, IBM and DEC. At this time, we are seriously considering the Silicon Graphics Power Onyx primarily because of its cost effective floating point performance, but also because of its graphics features. Our proposed budget is based on the purchase of an SGI Power Onyx system with eight R8000 90 Mhz processors, 2 GByte high density memory, Reality Engine graphics hardware, and 64 GBytes of magnetic disk storage.
