Techniques for tamper detection of a memory module having non-volatile memory devices resident on a printed circuit board (PCB) by circuitry of a controller also resident on the PCB. Examples include determining resistance values of a character pattern sprayed on a side of a cover facing the non-volatile memory devices using conductive ink following first and second boots of the memory module and asserting a bit of a register to indicate tampering of the memory modules based on a comparison of the resistance values. Tamper policy actions may be initiated based on detection of tampering.