SanDisk have updated their SSD lineup with the X400 family, available in sizes of 128GB, 256GB, 512GB and 1TB all of which are available in 2.5" and M.2 form factors.  They have continued their tradition of adding a small SLC flash cache to the drive, with the majority of storage being TLC.  Inside you will find Marvell's 88SS1074-BSW2 four channel controller and 256MB of DDR3L-1600 and as you can see, a lot of extra space.  SanDisk also united their SSDs lines in the 400, with 256-bit AES on these drives there is unlikely to be a new generation of the 300s.  Check out KitGuru for the full performance numbers of this consumer level SSD.

"The X400 family features SanDisk’s 6th generation 15nm Triple Level Cell TLC NAND and just like the previous X300 uses SanDisk’s nCache technology where some of the NAND runs in SLC mode to bolster performance."

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