We had installed one cpu to the tyan Dual Socket motherboard. Our applications require that we install a second cpu to the motherboard. Do we need to reinstall the OS (Windows Server 2003 Standard x64). If the addition of the second CPU can be done without the reinstallation of the OS then what is the best practices for doing so. Will the system behave the same as it did the first time post Installation of OS with Single Processor installed.