If the era of the 15,000 RPM drive is not over officially, it will be soon. Solid-state drives (SSDs) have increased their durability and capacity to the point they are completely viable replacements for the high-speed drives, which were used to store "hot," or frequently accessed data.
The latest example of the 15k drive killer comes from Dell, which has introduced SSDs of up to 3.8TB across its entire storage portfolio. Dell is using the new Triple Level Cell (TLC) 3D NAND technology from Samsung, which makes the memory used in SSDs cheaper and easier to produce.
3D NAND flash memory stacks memory cells on top of each other, which allows for more transistor gates in the same piece of silicon. This translates into increased capacity per chip. Flash pricing has struggled to match HDD pricing because the HDD industry has for years found new ways to squeeze more bits onto the same two or three platters found in a 3.5-inch drive. Doubling capacity of a hard drive meant maybe a 30% price increase. Doubling capacity of an SSD meant doubling the price.
Thanks to the 3D stacking, Dell now claims it now offers the cheapest flash in the industry. For example, its Dell Storage SC4020 enterprise-class all-flash solutions are available for as low as $1.66 per gigabyte street price and as low as 58 cents per gigabyte for typical hybrid flash configurations.
The higher memory density means the SC Series arrays can squeeze up to 90 terabytes of raw flash capacity into a 2U box, twice the capacity of previous generations.
One of the things that have kept 15k drives going is their price advantage – about one-tenth the price per gigabyte of SSD, according to market research firm IHS -- but this announcement puts 15k drives and SSD closer to parity, according to IDC.
"Dell’s announcement of flash drives built on TLC 3D NAND technology puts them in the storage density lead at 45TB per rack unit for flash-based arrays and drops the dollar per gigabyte cost of enterprise flash storage to roughly the same cost as 15K RPM HDDs, with significantly higher performance,” said Eric Burgener, research director, storage systems, IDC in a statement.
So it looks like one more step forward for flash and one step backward for spinning media.