Solid-state drives (SSDs) are much faster than spinning hard drives, but many of us still keep a few mechanical hard drives around for bulk storage. While you can get SSDs with a terabyte or more space, they’re extremely expensive. Meanwhile, spinning drives are creeping up past 12 terabytes. A new round of NAND flash production at Samsung could finally make SSDs in the multi-terabyte range affordable and mainstream. Maybe you’ll be able to ditch those spinning drives before long.
Samsung says it has started production on 4-bit quad-level NAND cells (QLC), which stores more data in the same space as older 3-bit NAND cells (TLC). This chip design will end up in consumer SSDs as a 1Tb (terabit) 4-bit V-NAND chip. Stack enough of those together, and you can get a lot of storage in the standard 2.5-inch SSD form factor at lower costs. Samsung expects mass production to start around the end of the year.
A major impediment to making 4-bit NAND a reality has been the substantial performance hit due to lower charge levels. As the chip capacity per unit area rises from 3 to 4-bit, electric charge can decrease by as much as 50 percent. That charge is used to read information from a sensor, so it’s much more difficult to maintain performance over time. Samsung says its 4-bit quad-level cells (QLC) drives will have the same or better performance as 3-bit SSDs thanks to a 3-bit controller and “TurboWrite” technology. TurboWrite runs a small portion of the SSD in as cache to speed up drive performance. Overall, Samsung claims sequential read speed of 540 MB/s and a sequential write speed of 520 MB/s in 4-bit SSDs.
Consumers will have the option of picking up the new Samsung SSDs in 1, 2, and 4TB capacities. The 2 and 4 TB drives will still be a bit spendy, but the 1TB tier should offer a solid price advantage over current 1TB solid-state drives. You’ll spend close to $200 for a 1TB SSD right now from top brands. That same money would buy you a 6-8 TB spinning drive. Samsung hasn’t announced specific pricing, but 4-bit cells should narrow the gap a little.
Samsung is also planning to use its 4-bit V-NAND chip in microSD cards. It’s planning a 128GB card that would offer better performance than current products. New M.2 SSDs with the QLC technology are also in the works, but these will first come to enterprise applications around the end of the year. Consumer versions will come later.