Actually, Intel has been almost totally opaque about what 3D XPoint is, except it&#x27;s not a phase change media like that is used in optical disks, and per  <a href="https:&#x2F;&#x2F;news.ycombinator.com&#x2F;item?id=10366907" rel="nofollow">https:&#x2F;&#x2F;news.ycombinator.com&#x2F;item?id=10366907</a> &quot;<i>We learned that 3D XPoint used a bulk material property change (rather than a stored charge) to address each cell.</i>&quot;