Memristors are completely powered off when not accessed, making heat scale entirely with access speed, not chip size. Also, memristors are not stacked, they ar

Memristors are completely powered off when not accessed, making heat scale entirely with access speed, not chip size. Also, memristors are not stacked, they are deposited on a surface a layer at a time. This is a meaningful difference -- stacked chips are much harder to manufacture, and have much worse thermal conductivity than what is essentially a solid chunk of TiO2.