Introduction, Specifications and Packaging
Same speedy SSD, smaller form factor!
Following the same pattern that Samsung led with the 840 Pro and 840 EVO, history has repeated itself with the 850 Pro and 850 EVO. With the 850 EVO launching late last year and being quite successful, it was only a matter of time before Samsung expanded past the 2.5" form factor for this popular SSD. Today is that day:
Today we will be looking at the MSATA and M.2 form factors. To clarify, the M.2 units are still using a SATA controller and connection, and must therefore be installed in a system capable of linking SATA lanes to its M.2 port. As both products are SATA, the DRAM cache based RAPID mode included with their Magician value added software is also available for these models. We won't be using RAPID for this review, but we did take a look at it in a prior article.
Given that 850 EVOs use VNAND – a vastly different technology than the planar NAND used in the 840 EVO, we suspect it is not subject to the same flash cell drift related issues (hopefully to be corrected soon) in the 840 EVO. Only time will tell for sure on that front, but we have not see any of those issues present in 850 EVO models since their launch.
Cross sectional view of Samsung's 32-layer VNAND. Photo by TechInsights.
Samsung sampled us the M.2 SATA in 120GB and 500GB, and the MSATA in 120GB and 1TB. Since both are SATA-based, these are only physical packaging differences. The die counts are the same as the 2.5" desktop counterparts. While the pair of 120GB models should be essentially identical, we'll throw both in with the results to validate the slight differences in stated specs below.
EVO line products use TLC flash for storage, with a small SLC caching portion that handles all incoming data. The only time writes are directed straight to TLC is when the buffer has been completely filled, which is very rare as that buffer is aggressively written back to the TLC area whenever possible. Here are the TurboWrite specs:
Simple packaging for both variants. Essentially white box with a nice graphic and logo.