RAM = accessible anywhere (very simply put) D = Dynamic = loses data if power is gone

This is NVRAM tech, NV standing for ‘non volatile’. That means it keeps the data if power is lost. You only need to re-write if you read that data. There is probably a hardwired option to do this immediately, perhaps even capacitors to ensure this goes through even if you happen to lose power that very moment.

Consumes extra energy, may add some latency to reads, but there’s more to being fast and non-volatile at the same time. May be wort it, may be not.