In a method and a device for determining requirement parameters of at least one physical hardware unit, the operating parameters of simulated, virtual hardware units are varied during the execution of a program flow on the virtual hardware units, for example via an interface device of a simulation device, in such a manner that requirement parameters of the execution of a program flow of at least one physical hardware unit can be identified. A method and a device are used for determining requirement parameters of at least one physical hardware unit. The method and the device are used to determine requirement parameters of software products of hardware components to be used. Requirement parameters are allowed to be identified systematically, using an operating system and eliminates the need for expensive, physical hardware components and for modifications to a physical computer system.