A magnetoresistive memory device that stores data in the synthetic antiferromagnet (SAF) included in each spin-torque memory cell provides for more robust data storage. In normal operation, the memory cells use the free portion of the memory cell for data storage. Techniques for storing data in the reference portions of memory cells are presented, where an unbalanced SAF that includes ferromagnetic layers having different magnetic moments is used to lower the switching barrier for the SAF and allow for writing data values to the SAF using lower currents and magnetic fields than would be required for a balanced SAF.