Review: Samsung 850 Pro 512GB SSD
Reviewed by: Wendy Robertson
Provided by: Samsung
Firmware version: EXM01B6Q
Back in July 2014, I reviewed the 1TB version of the Samsung 850 Pro SSD. The unit I tested was a pre-production test sample. Now I’m reviewing the Samsung 850 Pro 512GB SSD, and this time it’s a production sample, which Samsung has sent me for long term testing.
In order to conduct a long term test, one must first investigate how an SSD behaves when it’s new, hence this article.
The Samsung 850 Pro is the world’s first SSD to use 3D V-NAND which is quite different from the normal planar type NAND used in other SSDs.
It was no secret that Samsung had been working on a new type of NAND, dispensing with the ‘planar’ arrangement and the ‘charge pump device’ (CPD), by moving to a 3D vertical stacking cylindrical cell arrangement (V-NAND) where the cells are stacked vertically, with up to 32 layers, allowing a much higher density. In V-NAND, the CPD is also gone, being replaced by a Charge Trap Flash (CTF). A CPD stores the charge in a semiconductor where imperfections in the material can cause electrons to leak, thus reducing NAND endurance. A CTF stores the charge in the isolating layer, where leakage is not a problem. A CTF also requires much less voltage to store the charge, so as an added benefit, V-NAND requires much less energy to store the charge.
Moving to a vertical cell stacking arrangement rather than the planar design also has a huge advantage. Because stacking cells vertically takes up less space, it allows Samsung to take a step back in the cell node size, so instead of shrinking the current 19nm node size, Samsung have been able to use a larger node size, most likely around 30nm. Increasing the node size means better endurance. Couple the new CTF method of storing the charge with the increased node size, and Samsung estimates that V-NAND could have as much as ten times the endurance of NAND based on the 19nm planar design.
Another advantage of using a larger node size, is NAND page programming times are reduced substantially. Typically, 19nm planar NAND takes around twice the time to program a NAND page when compared to 30nm 3D V-NAND. The end result is you get higher performance which is much more sustainable.
So let’s find out how this new SSD performs in our range of tests.
Samsung company information
Samsung should need no introduction, but those of you who would like to find out more about Samsung, can do so at their website.
The Samsung 850 Pro 512GB SSD
Now it’s time to take a look at the drive itself and what it came shipped with.
Now let’s head to the next page, where we look in more detail at the Samsung 850 Pro 512GB SSD…..