James P. Hogan's Entoverse : a Giants novel

Human society on Jevlen was falling apart -- and it looked as if JEVEX, the immense super-computer that managed all Jevlenese affairs, was at the heart of the matter. Except that the problems didn't stop when JEVEX was shut down. People were changing -- or being changed. It was almost as if the Jevlenese were being possessed..