I don't trust wiki, give me a credible source
on a side, the one huge downside to DRAM based, or even SRAM, is that when it loses power, all data is lost. great if you just want speed, but if you need to preserve your data, and need to be sure that the data will always be on that little iron disk, it's no good. Oh, oops...the battery died, well there goes my life!
However, you are right, DRAm/SRAM based are not limited to write cycles, as they're nothing more than several sticks of ram shoved in a box with a controller.
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