2nd 840 Evo Fix Is Here

[SteelCrysis]

Are you kidding?  Samsung gets a free pass, and TLC's failure to penetrate is scapegoated on another controller: http://www.anandtech.com/show/9165/silic...r-everyone

The SSD industry has been talking about TLC NAND for over three years now. We published our first post, Understanding TLC NAND, back in early 2012, but in three years we have actually seen very little TLC NAND making it to the SSD market. Samsung was an early adopter by introducing the SSD 840 in September 2012, but Samsung has always been a special case as its SSD business is fully vertically integrated. When you design and manufacture everything in-house, it's obvious that you will have a technological advantage when it comes to adopting new technologies.

TLC is tightly linked with both controller technology and NAND production because TLC inherently has a higher error rate, which needs a stronger controller (although admittedly Samsung has had some issues with TLC). The lack of proper controller is the reason why other NAND vendors haven't invested as heavily on TLC as Samsung because Micron, SanDisk and the like have to rely on whatever third party controllers are available on the market. Without a high volume product to put your TLC NAND into, it means that there's no reason to produce TLC in a large scale, which defeats the cost savings that TLC bring. Micron tried to promote its 25nm TLC NAND for a while a few years ago, but it quickly realized that the available SSD controllers aren't capable of creating a reliable product -- at least not one that would bring any cost savings since the drive would need serious over-provisioning for endurance and ECC parity.

Due to the lack of controller support, nobody other than Samsung and SanDisk have a TLC SSD on the market, although SanDisk had to rely on heavy over-provisioning with 5:1 parity ratio since the Marvell controller used in the Ultra II wasn't designed with TLC in mind. Silicon Motion's SM2256 will be the first commercially available controller and firmware combo with TLC support and today we are taking an early look of the platform in the form of a reference design sample. ADATA already announced its SP550 SSD that will be based on the new SM2256 controller and available later in the summer, but given how many OEMs rely on Silicon Motion's controllers nowadays we will likely see a large number of SM2256 based TLC drives entering the market by the end of the year.

Of course, they have to throw in a brief caveat at the end:

In any case, it will all boil down to pricing anyway. If Silicon Motion's OEM partners can drive the prices down with the SM2256, I will be totally fine with the performance because the SM2256 is still more than fine for basic usage. TLC SSD pricing was actually one of the things I was very vocal about at Computex because OEMs can't price their TLC drives similarly to the MLC ones and expect it to be a good sale. TLC isn't as good as MLC and that's a fact that nobody can deny. Especially after Samsung's issues with TLC the market has become more skeptical about TLC in general, so saving a few bucks isn't enough anymore for the educated buyers to choose TLC over MLC -- I think the difference has to be in the order of 10% or so to be worth the lower performance and possible long-term reliability risks that TLC brings. I do believe that the SM2256 is a vehicle capable of delivering such cost savings, but for now we will just need to wait and see what happens.