Impedance matching device for high speed memory bus

The present invention relates generally to personal computers and in particular to memory buses in personal computers. A memory bus impedance matching module is inserted in each empty memory expansion socket on a computer memory bus to provide a constant impedance on the bus. Impedance devices, such as non-functional memory devices, are mounted on the module housing and coupled to standard bus communication line connections on the module housing. The modules are placed on the memory bus to prevent communication errors without needing to fill each expansion socket with real memory.