Conclusion
We haven't had a lot of luck with Micron's new 3D NAND. Micron hasn't even released a consumer SSD with its 3D MLC, and the MX300 with 3D TLC was a disappointment. We've tested several products with Micron's 3D NAND in both MLC and TLC forms, but if you already own an SSD large enough to satisfy your needs, none have been noteworthy enough to merit an upgrade.
3D NAND has yet to deliver increased capacities because strong flash demand coupled with the shortage has made high-density NAND packages incredibly expensive. That's prevented significant price reductions. Micron's 3D NAND trades performance compared to older planar NAND, but users don't receive capacity and pricing benefits.
Adata's XPG SX950 is the best example of what's possible with 3D NAND, but the SX950's increased performance has less to do with the flash than it does with Silicon Motion's commitment to squeeze out extra performance. We've tested Micron's flash with several controllers, and the SM2258H's firmware is by far the best to date. The controller and new programming features make the SX950 the best of this new class, but it still doesn't dethrone the 850 EVO. We do finally have higher performance, which is the one area many of us are willing to trade off slightly for increased capacity.
With new technology, the adage of one step forward, two steps back often applies. The transition to 3D NAND has been like stepping two years back, though. The Adata XPG SX950 is the first SSD to take those first two steps forward, but we're just now getting back to where we were before 16nm planar NAND. The Adata XPG SX950 is the first consumer SSD to use Micron's 3D NAND to regain equal footing with popular older SSDs. It's obvious progress, but Micron's first-generation 3D NAND still isn't comparable to Samsung's V-NAND technology.
At the time of writing, the Adata XPG SX950 480GB is $249.99 at Newegg. The Samsung 850 EVO 500GB retails for $199.99 at Newegg, but B&H has the drive for $169.00. That's the best price we've seen, and it includes free shipping. We like the Adata XPG SX950 480GB, and it's a viable alternative to the 850 EVO 500GB. We just don't see a reason to purchase the SX950 over the 850 EVO, even if they carry the same price tag.
Adata's done quite a bit to make up the performance delta between the industry go-to and the SX950. The new drive features a full six-year warranty and covers up to 800TB of endurance (for the 960GB model). The drive also includes an ample accessory package that includes a desktop adapter bracket, disk cloning software, and a software toolbox to monitor and manage the drive.
We like the Adata XPG SX950 and feel the company made the best product it could with the tools and hardware available. The problem we have, and the problem everyone else has had for the last several years, is the Samsung 850 EVO. Companies are still building products to match or come close to the EVO and have to tack on extras to fill in gaps. The goal shouldn't be to match the 850 EVO but to surpass it.
The influx of quality NVMe SSDs also cost nearly the same as SATA-based devices but deliver a better user experience. The NVMe XPG SX8000 512GB ($211.99) actually retails for slightly less than the XPG SX950 480GB. The XPG SX950 is a good product, but it has some gaps that need to be filled. The first one is pricing.
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