SanDisk Ultra Plus SSD 128GB Review

Internally, the Ultra Plus 128GB SSD is tiny, most of the casing is empty space.  The PCB is home to two MLC 19nm 64GB NAND modules (0531 064G), a Marvell 88SS9175-BJM2 4 channel Controller, and Samsung K4T51163QJ-BCF7 (32Mx16 = 512MB) DDR2-800.

Oddly enough, most of the information I have found around the web indicates that these drives are fitted with Samsung 128MB DRAM, yet searching on the model in this SSD indicates that this is a 512MB module.  Samsung Product Detail Page

With this new 19nm MCL, SanDisk is quietly trying to do something different, nCache. The graphic below illustrates that between the MLC (Multi-Level Cell) NAND and the DDR DRAM is something called nCache or SLC (Single-Level Cell) Cache.  Quick Lesson: In SLC only 1 bit is stored in 1 cell and 2 bits are stored in 1 cell in Multi-Level Cell designs.  SLC is faster…  However, this isn’t true SLC; SanDisk has designated an area of MLC to for the controller to use as SLC by writing only 1 bit per cell, thus nCache.