replace flash in certain roles, and some even claim to be a truly universal memory, offering the performance of the best SRAM devices with the non-volatility of flash. As of June 2018, these alternatives have not yet become mainstream.

Those who required real RAM-like performance and non-volatility typically have had to use conventional RAM devices and a battery backup. For example, IBM PC's and successors beginning with the IBM PC AT used nonvolatile BIOS memory,