Aspects of the invention include a computer peripheral device comprising an input element that operates based on a performance characteristic, an electropermanent magnet (EPM) assembly including a permanent magnet configured to generate a magnetic field and a magnetizing assembly configured to set an intensity of the magnetic field generated by the permanent magnet, and a magnetorheological (MR) material coupled to the input element. The MR material has a viscosity that changes based on the magnetic field and affects the performance characteristic of the input element.