DRAM retains its contents for several seconds after power is lost. Although DRAM becomes less reliable when it is not refreshed, it is not immediately erased, and...J. Alex Halderman, Seth D. Schoen, Nadia Heninger, William Clarkson, William Paul, Joseph A. Calandrino, Ariel J. Feldman, Jacob Appelbaum, Edward W. Felten From Communications of the ACM | May 2009