A computer system comprises a plurality of field replaceable units (FRUs) for supplying processing resources and a system controller. Each of the plurality of FRUs has a field replaceable unit identification (FRUID) memory adapted store a capacity-on-demand (COD) indication associated with the FRU, wherein the COD indication is indicative of whether the FRU is a base level resource or a COD resource. The system controller is configured to access the FRUID memory of each of the plurality of FRUs to detect the COD indication. Additionally, the system controller is configured to enable at least those of the plurality of FRUs for which the corresponding COD indication indicates that the FRU is a base level resource. The system controller is further configured to identify a need for additional processing resources, and is configured to enable additional ones of the plurality of FRUs responsive to identifying the need for additional processing resources.