We have a newer Two socket server with Quad Core processors. On this server we are running two instances of Sql 2000 SE SP4 and the Server OS is Windows 2003 Enterprise with service pack 1. The server has 8GB of ram. The question is should we set each instance of SQL to run on seperate processers under Processor Control. Currently each instance is set to use all available processors and the minimum query plan threshold is set for 5. Would there be any performence gains if we divided the processors between the two Sql instances?