We recently published a review of the CS2211 SSD from PNY's premium XLR8 line. The CS2211 is aimed at gamers and enthusiasts, and uses Toshiba 15nm MLC flash. The CS1311 we're testing today employs Toshiba's 15nm TLC NAND for more value-oriented shoppers. PNY's PS3110-S10-powered drive uses Phison's new direct-to-die sequential write algorithm to increase performance, so we're anxious to see what it can do.
TLC-based SSDs from every company other than Samsung are slow compared to drives armed with MLC and SLC flash. In fact, they set SSD performance back several generations in some very common workloads. Not every application suffers, but you'll notice big software installations slow to a crawl, for instance. Depending on the flash used, you'll see sequential write speeds drop as low as 70 MB/s after a couple of seconds—that's less than a modern disk-based hard drive!
Phison is the first controller vendor aside from Samsung to address the issue. By using an approach called direct-to-die, sequential data fills the SLC buffer first, and then begins to write directly to the flash. Without the direct-to-die algorithm, information would pass to the small SLC buffer area and then "fold" into the NAND. The buffer needs to purge its data to the flash before accepting more. Usually this happens quickly, so you don't notice a pause during the transfer. But it does affect performance. By skipping over the buffer and writing straight to the NAND, sequential write performance more than doubles on high-capacity SSDs. Lower-capacity drives don't benefit as much, but they're still a lot faster in those operations.
The CS1311 uses Phison's new direct-to-die algorithm, but that's not its only compelling feature. When manufacturers realized that TLC-based SSDs were not popular with mainstream users, their prices dropped quickly. When you consider that value proposition and improved performance together, drives like the CS1311 start looking like solid additions to mid-range PCs.
PNY released the CS1311 at four capacity points, and we're surprised to see a 120GB model in the group. Many companies have dropped that size altogether. Given 128Gb density, there are only eight dies in a 128GB-class SSD, which means write performance outside of the SLC buffer is very low. PNY rounds out its CS1311 family with more interesting 240GB, 480GB and 960GB models.
The performance claims differ slightly for each size. Sequential reads hold steady at 550 MB/s for all four models, while sequential writes range from 510 to 520 MB/s. Random I/O also varies a bit depending on the configuration you're looking at, but you won't be able to tell under real-world conditions.
We detailed many of the Phison PS3110-S10 features in a controller-specific story. You can read more about the eight-channel controller here.
Pricing, Warranty And Accessories
The CS1311's strongest feature is its price. PNY is very aggressive here, achieving close to 25 cents per gigabyte for three of its four capacities. At those levels, TLC-based SSDs become more attractive to folks who might have previously eschewed them.
PNY covers its CS1311 family with a three-year warranty that doesn't seem bound by endurance. We searched through the company's stipulations on its website and couldn't find specific mention of a terabytes-written (TBW) limit or any strings tied to the WMI.
Unfortunately, PNY doesn't offer a storage utility apart from a firmware update tool. Phison does though, and it's readily available online. We confirmed that Phison's utility does work with the CS1311 SSDs. PNY does include Acronis True Image HD with this model, and the software key is located in the bundled paper manual.
A Closer Look
PNY sells SSDs online and in stores like Best Buy or Fry's Electronics. The company conveys a lot of information on its retail package, including some performance data that makes shopping in a retail environment easier.
The CS1311 doesn't include a lot of extras, though that's standard practice for low-cost SSDs these days. You get a paper product manual with a code for Acronis True Image HD, plus a 7mm to 9.5mm adapter.
Not that it affects performance, but PNY's CS1311 is a good-looking piece of hardware. It employs a metal chassis with a graphic sticker on the front and another on the back with information printed on it. The back of the drive also has model and serial number info for warranty purposes.
Like most modern SSDs, the CS1311 fits in a 7mm-tall enclosure so it's compatible with the latest notebooks that require low-profile storage.
Both of the CS1311 drives we received for review (240GB and 480GB) host eight flash packages. The 240GB model uses a smaller PCB that it shares with the 120GB implementation, while the 480GB drive shares the same PCB as the 960GB flagship. The larger drives in each of the two groups simply populate more of the pads with flash packages.
The printed circuit boards appear to be identical to Phison's reference design. We've tested several SSDs with the S10 controller now, both with MLC and TLC NAND. Thus far, we haven't encountered any issues with them, nor have we heard any complaints from actual owners.