1. A system comprising: a computer comprising: a system serial number; and a broken hardware unit comprising: a non-volatile memory unit comprising a read/write non-volatile memory field; and enablement definition data relating to functions of said broken hardware unit; a power unit adapted to start said computer; a first control mechanism adapted to enter a serial number in said read/write non-volatile memory field; a second control mechanism adapted to read said read/write non-volatile memory field; and a processor adapted to match said serial number of said read/write non-volatile memory field with said system serial number.