We tested the Samsung SM951-AHCI when it first came to market last year in the Lenovo X1 Carbon Gen 3. The SM951-AHCI suffered from a low thermal throttling threshold when it first shipped with the initial firmware. Lenovo issued a firmware update roughly a month later, which brought the drives up to the same firmware revision that RamCity was already shipping with its SSDs. Lenovo continued to release updates with small tweaks, and those revisions worked on all SM951-AHCI drives regardless of where users purchased them.
The SM961 we tested today shipped with firmware CXA7100Q and we're fairly sure it is the first mass production firmware. In time, we should see performance-tuning updates for this product, as well. The SM961 is the first SSD from Samsung to utilize new 256Gbit MLC NAND die so we fully expect some tweaks in the coming months.
The SM961 NVMe SSD has a lot of potential. We called it a fire breather because it smokes everything available in many of the four corner tests. The underlying architecture has some not-so-obvious limitations, though. These limitations are the kind of issues we usually see massaged out over time with optimized firmware.
Right now, the SM961 is a very good SSD. If your workload involves heavy sequential data transfers, such as audio or video production, large batch image editing or similar workloads, then you can't choose a better SSD for the job. Day-to-day desktop workloads will not see a large performance benefit over the retail 950 Pro 512GB, but you will not notice a difference between the two without a quick hand and a stopwatch.
The SM961 brings the obvious 1TB capacity benefit to the model we tested today. The Samsung 950 Pro does not ship in 1TB capacity, so it's a fairly cut and dry issue. The SM961 1TB sells for $512 and doubles the capacity of the 950 Pro 512GB that sells for $319. You get more bang for your buck with the SM961; it's simply a better value.
There are only two 1TB NVMe SSDs available at this time. The OCZ RD400 was the first to come to market and it currently sells for $770 at Newegg, while the Samsung SM961 1TB sells for $512 (just 50 cents per gigabyte). Some may say the price is still high compared to low-cost TLC products, which companies are giving away today for 25 cents per gigabyte. If you don't want (or need) the best performance and very low latency then don't spend the extra money for it.
The SM961 will not offer a large performance increase under very light workloads. However, when you ask for high-performance the SM961 will deliver, while the TLC-based SSD will drop to native NAND speeds when it exhausts the SLC cache. It may be difficult to imagine, but the SM961 will provide a 10 to 15x performance increase over TLC drives when writing large volumes of sequential data. That's a bigger difference than comparing the first consumer SSDs to hard drives.
In the coming weeks, we'll test the SM961 in 512GB and 256GB capacities. This will allow us to compare Samsung's 3rd generation PCIe controller on equal ground to the first- and second-generation controllers. We're excited to compare the XP941 and SM951/950 Pro to the new SM961, which features the most advanced controller in the Samsung portfolio.
There are a couple of issues that Samsung should address. The first is the lack of Rapid Storage Technology (RST) RAID in Z170 chipsets. Oddly enough, this is not a Samsung issue according to OCZ (a Toshiba Company). We first learned of the issue with the OCZ RD400, but experienced it ourselves for the first time with the SM961 in RAID 0. Users can still chose to run a software RAID 0 array with Windows or another compatible operating system, but Windows will not boot from a software RAID volume. To be fair, this is neither a Samsung nor OCZ issue.
The other negative for the SM961 has been around for several Samsung OEM SSD generations. The OEM products do not support Samsung's excellent Magician software. Samsung didn't enable Rapid Mode (a DRAM cache feature) for the 950 Pro, either, so you are not gaining the best feature for either drive. We wish Samsung would just enable Magician for all Samsung SSDs - regardless of the team that brought the product to market. I'm sure the OEMs would like access to the value-add software, too.
The first batch of Samsung SM961 SSDs has already shipped from RamCity and the next round is on the way. We've ordered from RamCity in the past and have always been happy with our purchases. The company is at the forefront of SSD technology and the support team is very knowledgeable; the company even releases instructional videos for advanced installations.
Your best bet to secure a drive is to preorder rather than waiting for the supply to meet demand. SM961 availability will get better in time, but right now, you will have to wait in line. The line started forming before this review, and we suspect it might grow longer after you read this.