Datasets that are larger than texture memory must be handled in pieces, which results in severe performance penalties. Direct volume rendering enables visualization of information that can not be satisfactorily represented by surfaces. The problem is how to do it quickly. Graphics workstations are not the solution. They are optimized for rendering shaded texture-mapped triangles.
Triangles are special because they have a compact representation.
This compactness is what makes dedicated hardware pipelines feasible. Volumetric datasets, on the other hand, are not compact. They are orders of magnitude larger than surface representations. These PCs are part of the existing university computing infrastructure and are already connected to the campus network. The superdisplay utilizes the existing university computing infrastructure.