The 950 Pro isn’t Samsung’s first consumer M.2 SSD, or even the company’s first PCIe M.2 drive. It is, however, Samsung’s first consumer M.2 and NVMe drive that uses the full performance of four PCIe 3.0 lanes. It is also an upgrade from its predecessor, the SM951, in that it uses 3D V-NAND rather than planar NAND.

Somewhat disappointingly, the 950 Pro comes in only two capacities for now: 256GB or 512GB, with a 1TB model promised for next year. Samsung is resolute in only producing single-sided M.2 devices to keep the drive’s thickness to a minimum, so the 1TB drive will have to wait until 48-layer 3rd-generation V-NAND is available. Thankfully, no 128GB model will be sold, indicating that 128GB SSDs may be on their way out.

UK pricing is pegged at £150 for the 256GB model and £270 for 512GB; in the US, it's $200 and $350, respectively. As always, expect some variation between retailers with these prices, and in these early days, prices may be slightly higher than what Samsung is quoting. We're told that the 950 Pro will hit retailers today; we'll update this story with some links when they first appear.

Updated: Scan now has the 512GB 950 Pro in the UK—but they're charging a rather shocking £320 for it, which is well over the RRP. In the US, Newegg has the 512GB drive at $350.

If you just want the 950 Pro benchmarks, you can skip the following section. If you want a bit of background on the state of the SSD market, and why Samsung seems to be absolutely dominating at the moment, read on!

The state of Samsung

Samsung is the world’s largest producer of NAND flash memory, and is (still) the only firm to sell SSDs with a controller and firmware developed in-house, using NAND flash memory manufactured at its own fabrication plants.

Working on everything in-house has already paid dividends for Samsung. With the 850 Pro, released last year, the company was first to bring 3D flash memory technology to market, which it calls V-NAND. Put simply, with 3D NAND flash memory, the memory cells are stacked in three dimensions, with a far greater number of connections between them than is possible with a 2D planar arrangement. One of its biggest potential advantages is greater densities from a single chip, but also it seems Samsung hasn’t been forced to use ever smaller process nodes like its competitors. The 850 Pro is based off 40nm NAND flash memory, while other firms are forced into using smaller 20nm, 19nm, and 16nm chips to increase densities.

In response to Samsung's performance in the solid-state storage arena, the rest of the industry is consolidating its forces. Intel has strengthened its relationship with Micron, announcing its own 48-layer 3D flash memory, and what appears to be a very interesting technology called 3D XPoint. Said to be non-volatile and 1,000 times faster than NAND, while still offering a higher density than DRAM, Intel is describing 3D XPoint as a whole new category of memory, due to ship next year. But as of now, few concrete details are known about 3D XPoint products.

Separately, Toshiba—another large producer of NAND flash memory—is slowly moving towards the same route of vertical production. It now owns OCZ Storage Solutions, and as seen with the recent entry-level OCZ Trion 100 SSD, which uses a Toshiba-designed TC58 controller, is moving towards an SSD made entirely in-house. They’re not quite there yet though, particularly since OCZ still operates relatively independently of Toshiba.

Samsung’s current flagship 2.5-inch SATA SSD, the 850 Pro, is probably the most advanced SATA drive on the market. With 32-layer V-NAND, read and write performance that hovers around 550MB/sec, a 10-year warranty, and capacities that go up to 2TB (and a 4TB model due out next year) it’s a very impressive device. But all this technology doesn’t come cheap: the 850 Pro is one of the most expensive 2.5-inch SSDs on the market.

A more budget-friendly drive, the 850 Evo, aims for a more mainstream price point. It likewise uses V-NAND, but with 3-bit MLC flash memory for cost reduction and a large SLC cache, rather than 2-bit MLC as with the 850 Pro.

Herein lies a problem for Samsung. Other firms are competing with ever-cheaper products at entry-level prices. Crucial (a subsidiary of Micron) released the MX100 last year, which it has now followed up with the BX100 and MX200 drives, all of which cost less than Samsung’s drives, and for most people are absolutely sufficient. There’s a chance that such a race to the bottom could see Samsung’s market share slowly eaten away by ever-cheaper drives.

While Samsung has the advantage on paper, it’s difficult to argue that the performance advantage of the 850 Pro is worth the cost; in a blind test, you’d be hard pressed to tell the difference between the 850 Pro and another cheaper SSD. Even in synthetic benchmarks, the gap between the 850 Pro and other drives isn’t enormous.

You might think that Samsung's next step would be to produce a cheaper drive, to compete with the Crucial and co.—but no, it's quite the opposite: With the 950 Pro, announced today, Samsung is doubling down on performance. I think that's our cue to get back to the review.

Orestis Bastounis

Orestis Bastounis







Too many TLAs

The new 950 Pro occupies a slightly odd space in the company's overall SSD lineup. Samsung’s alternative consumer M.2 SSD, the 850 Evo M.2, is not in the same performance category as the 950 Pro. M.2 SSDs can use either the PCIe bus or SATA bus, and the 850 Evo is a SATA 6Gbps drive—it's no faster than a normal 2.5-inch SSD. Its main advantage is the smaller M.2 card form factor, which is of benefit in NUCs, Mini-ITX builds, or in ultra-thin laptops.

Spiritually, the 950 Pro is much closer to the NVMe variant of the four-lane PCIe SM951, which has on the market since earlier this year. Samsung originally intended for the SM951 to be an OEM-only product, included with retail PCs. Up until the launch of the 950 Pro, though, it was the best performing M.2 SSD on the market—and so, rather understandly, retailers have been selling them separately to PC building types. Being an OEM drive, the SM951 has a shorter warranty period, fewer support options from Samsung, and will not work with their Magician SSD management software.

With the launch of Skylake and the Z170 chipset, four-lane PCIe 3.0 M.2 storage is now available in a mainstream computing platform (assuming you categorise Haswell-E and X99 as intended for servers or workstations). Now is the perfect time for Samsung to launch a consumer PCIe M.2 SSD that makes use of this available performance, and the company has done just this with the 950 Pro.

The drive itself comes in the 80mm-long 2280 format. Every Z170 motherboard we’ve seen supports M.2 devices of this size, but the larger 110mm 22110 size is not universally supported. As with (we presume) all M.2 SSDs, it uses an M-key connector, which is mandatory for four-lane PCIe speeds. (For more information about the M.2 connector and its "keys," read our in-depth explainer.)

Notably, Samsung has opted to not bundle a PCIe adaptor card with the drive, something Kingston does with its Predator Hyper X M.2. While that would make the 950 Pro usable in any desktop computer right out of the box, it would mean higher pricing and more packaging.

The 950 Pro uses a 500MHz triple-core "UBX" controller, a small upgrade from the 400MHz "MEX" controller in the 850 Pro. Both capacities have 512MB of LPDDR3 memory (an upgrade from LPDDR2 in the 850 Pro) and both support the NVMe 1.1 protocol. AES 256-bit encryption is supported with TCG Opal and eDrive support promised, but only in a future firmware update.

The 950 Pro also has a technology called Dynamic Thermal Throttling, or DTT. While temperatures are not a particular concern for desktops, inside cramped smaller form factors they can be. Additional heat generated by a tiny M.2 storage device could cause problems. DTT is described by Samsung as a method for “controlling the temperature of the device to reduce overheating and maintain a high level of sustained performance.” There isn’t much additional info yet though, and this is not something we were able to test.

While the 850 Pro launched with an astonishing 10-year warranty, the 950 Pro only carries five years. But the quoted TBW (total bytes written) is higher on the 950 Pro than on the 850 Pro, with 200TB for the 256GB model and 400TB for the 512GB. This is a 33 percent increase over the 150TB offered by the 256GB 850 Pro and 300TB with the 512GB variant, which works out at roughly 109GB of writes per day for the 256GB model, and 218GB per day for the 512GB model, over a five year period. In nearly all "normal use" scenarios, it’s unlikely you’ll run into longevity problems with the 950 Pro (or really, any modern SSD).

Support for the 950 Pro is currently absent from version 4.7 of Samsung’s Magician software, but before launch Samsung sent us a beta of the 4.8 version of its software, which is due to be released soon. Samsung’s "Rapid Mode" memory cache system currently does not work in Magician 4.7 under Windows 10 either, and this is also to fixed in 4.8.

Magician is worth mentioning as it is (or will be) part of the overall offering. Other SSD manufacturers offer their own toolbox software as well, but Samsung’s effort is of a very high quality. It shows, at a glance, SMART data and drive health, with quick links to firmware updates, secure erase, and a benchmarking tool (which predictably, is slightly generous with the figures it gives Samsung-branded drives).

Samsung’s specifications state the 256GB 950 Pro uses up to 6.4W of power when active, with the 512GB model using up to 7W, with averages of 5.1W and 5.6W. Idle consumption is quoted at 70mW. It also supports DevSleep mode, with ultra-low consumption of just 2.5 mW. These figures will raise eyebrows as they’re higher than the 850 Pro, which Samsung quotes at 3.0W when in active use for the 1TB model.

Samsung is quoting sequential read speeds of (up to) 2,200MB/sec for the 256GB 950 Pro, and 2,500MB/sec for the 512GB model. 4KQD32 write IOPS are pegged at 85,000 for the 256GB drive and 110,000 for the 512GB, with read IOPS of up to 270,000 and 300,000 respectively.