In the past, people would try to make a form of non-volatile memory by connecting a static, volatile memory chip to a battery.

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And while DRAM is strong enough to handle complex software, it's slow: When the PC needs to crunch numbers, it must resort to far faster memory cache, also called SRAM (static random access memory).

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PUFs rely on the physical characteristics of SRAM (static random-access memory) technology.

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That said, PC Perspective has put in some quality time with the DDRdrive X1, which places 4GB DRAM and 4GB NAND in parallel on a full height PCIe card, keeping that volatile memory of yours safely backed up on a static disk, just in case.

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