Intel, Micron reveal Xpoint, a new memory architecture that could outclass DDR4 and NAND

For years, researchers have hunted for memory architectures that could address the primary weaknesses of DDR and NAND flash without introducing more problems or simply costing too much money. Today, Intel and Micron jointly announced that they may have created it.

 The new 3D Xpoint memory architecture is designed to address critical shortcomings of both NAND flash and DDR4. Let’s talk about how this new memory could address concerns in both markets.

The basics of Xpoint

3D Xpoint (pronounced “crosspoint”) is designed in a 3D structure, like some of the cutting-edge 3D NAND we’ve discussed. Unlike NAND, however, 3D Xpoint doesn’t use an electrical charge to store data in cells.
According to Intel, the properties of a 3D Xpoint cell change when the cell is written and remain changed for long enough for the device to be classified as non-volatile memory. Unlike NAND, 3D Xpoint memory can also write data into much smaller areas. NAND flash must be written in relatively large blocks (we covered this in our recent explainer on SSDs and NAND technology).
 


This image covers the basic features of 3D Xpoint. The new memory is designed to be non-volatile, stackable (to improve density), and can perform read/write operations without requiring a transistor (DRAM requires one transistor per cell, which is one reason why it draws much more power per GB than a NAND flash drive).


 Each memory cell can hold one bit of data, which might seem to be a disadvantage given that NAND flash can hold 2-3 bits per cell — but Intel is claiming that it can hit densities 8-10x greater than DRAM. Samsung has produced 8Gb DDR4 DRAM (that’s 1GB per IC), while Micron claims it can provide NAND chips at up to 2Tb. That’s 125x more dense than DRAM, and it implies that 3D Xpoint may not be all that dense compared with NAND flash.
Still, that’s a relatively small shortcoming if the other aspects of the technology pan out and the Intel / Micron alliance can stack the dies higher. The image below shows a pair of 128Gb 3D Xpoint dies; Intel claims that they’re smaller than competing DRAM designs and that the technology can be scaled to match NAND’s density in a similar footprint.