A security apparatus that can detect unauthorized alterations of physical arrangement of a computing system or unauthorized movements of a computing system through the use of acoustic signals is designed. Modules of a computing system including the security apparatus are able to generate acoustic measurements from received returned acoustic signals. Also, the modules are able to derive baseline acoustic measurements based on stored acoustic profiles. If, for any module of the computing system, its generated acoustic measurements do not substantially match its baseline acoustic measurements, the mismatch may indicate that there is an unauthorized alteration of physical arrangement of the computing system or an unauthorized movement of the computing system. Thus, the security apparatus in the module may take actions to prevent access to the sensitive data stored in the module.