By now Samsung has actually launched the first 2TB SSDs ‘Pro 850 2TB’ aimed at consumers. At last, the speed of solid-state flash memory has been combined with the multi-terabyte mass storage, that is previously been the preserve of conventional hard drives with their spinning magnetic platters.
Samsung has not revealed whether the new 850 Pro in 2TB format uses the same 40nm 3D memory. But given the density enabled by stacking multiple layers, it’s plausible that Samsung’s existing 3D V-NAND technology is good enough. However, what we do know is that achieving that headline 2TB has required Samsung to come up with a new controller chip.
Samsung says its existing MEX controller as seen in the existing 128GB to 1TB 850 Pro SSDs had limitations when it comes to really high capacities. Consequently, the new 2TB has a new controller, known as the MHX.
The elephant in the room and what we have not mentioned up to this point is that the 2TB model and indeed all Samsung 850 Pro and Evo models do not offer compatibility with the latest storage interfaces.
We speak of PCI Express-based interfaces like M.2 and SATA Express. Instead, the 850 Pro 2TB is a plain old SATA drive. What is more, SATA uses a control protocol known as AHCI, which was conceived for magnetic hard drives, not SSDs. And that, in turn, makes SATA sub optimal in terms of random access performance with SSDs.
In other words, it is simply bouncing off the limitations of the SATA interface. As for random access performance, we’re talking 41MB/s for reads and 133MB/s for writes, which are again as good as it gets for a SATA drive. The latest M.2 drives are up near 2GB/s for sequential reads and 200MB/s for 4k random writes.
So how you view this drive’s performance will ultimately come down to whether you’re in the market for M.2 or SATA drives. It’s great for a SATA drive, deathly slow in some departments compared to an M.2 drive.
- Capacity: 2TB
- Memory type: 3D VNAND
- Controller: Samsung MHX
- Interface: SATA 6Gbps
- Form factor: 2.5-inch
- Read / write performance: 550MB/s / 520MB/s
- IOPS performance: 100,000 read, 90,000 write
- Warranty: 10 years limited
Buckle up yourself for the trotting out of cliches. For if ever there was a horses for course verdict, this is it. Viewed in the broad context of all SSDs, the new Samsung 850 Pro 2TB is dead slow.
The latest M.2 drives absolutely annihilate it for raw performance. If you need the biggest and best SATA SSD for something like a laptop upgrade, this Sammy is a killer, albeit at a price.