“ Most people know that the contents of RAM are lost when a machine powers down. The paper notes, however, that this process isn’t instantaneous. In their tests, the authors found that various forms of RAM take anywhere from 2.5 to 35 seconds to reach a null state (newer RAM got there faster). That process is temperature-dependent; dropping the RAM to -50°C cut the rate at which memory was lost to 0.1 percent per minute. If that temperature seems hard to reach, it’s not. The researchers achieved it by turning a canned air dispenser upside-down and spraying it on the RAM chip. Dropping the chip in liquid nitrogen kept the error rate at a similar level for up to an hour.
