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Best NVMe SSDs

For decades, computer storage has been making huge strides in maximum capacities, but performance was falling far off the pace set by CPUs and GPUs. That all changed when flash-based solid-state storage (SSDs) hit the mainstream consumer market back in 2007. Those early drives were insanely expensive, and early adopters found that performance often degraded drastically over time, but they were the foot in the door.

By moving from the mechanical world of hard drives to the silicon world of SSDs, the industry experienced rapid improvements in performance, technology, capacities, and reliability. The SATA 1.5Gb/s bottleneck was quickly exceeded, followed by SATA 3.0Gb/s, and within a year of SATA 6.0Gb/s there were drives that could saturate even that interface. Faster alternatives were needed, but the interface was only part of the problem.

The other limiting factor was the command protocol, AHCI (Advanced Host Controller Interface), which was built to accommodate much slower media (e.g., spinning magnetic disks). AHCI ends up being inefficient when used with modern SSDs, and to get around these, a new standard was developed: NVMHCI (Non-Volatile Memory Host Controller Interface). NVM has 65K command queues with 65K commands per queue, compared to one queue with 32 commands in AHCI. It also has message signaled interrupts (MSI-X) and eliminates the need for synchronization locking when issuing commands. In short, it’s a much improved interface developed around the needs of flash memory rather than spinning disks.

NVMe drives do require motherboard BIOS support (if you want to boot from them), which generally means you need a relatively recent motherboard. Nearly all Z170 boards have NVMe BIOS support, and many Z97 and X99 boards will work as well. The latest motherboards also feature M.2 slots with x4 PCIe Gen3 interfaces, and this allows the use of an NVMe drive without taking up a lot of space. Just be aware that some boards (Z97 and X99 in particular) have M.2 slots limited to x2 PCIe Gen2 bandwidth, or 1GB/s, which will drastically limit the performance of the faster drives.

So, which NVMe SSDs are best? We’re skipping the enterprise-grade SSDs, as they’re far more expensive and if you’re in the market for that sort of drive, you should be running a server and will have a completely different set of requirements. 3.2TB with up to 743K IOPS, for only $8,000? Yes, please, we’ll take two. Quite a few new NVMe SSDs were announced at CES 2016 as well; we’ll update our recommendations as those launch and we’re able to test them. For now, here are the top three picks for consumer NVMe SSDs.

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Best Overall NVMe SSD

  • Excellent performance
  • Lowest price per GB for NVMe
  • M.2 available in many newer laptops
  • May throttle under heavy loads
  • "Only" 512GB

There aren’t too many options for consumer NVMe SSDs right now, and even fewer choices if you want an M.2 form factor. This can be particularly important if you want a fast SSD for a laptop, with many slim laptops only offering M.2 slots these days. For now, the first and only retail M.2 NVMe drives are Samsung’s 950 Pro drives, though we should see several more in the coming year. As one of the biggest names in the SSD market, Samsung has proven time and again that they know how to build a fast and reliable SSD. The 950 Pro 512GB is the current cream of the crop, sporting read/write speeds of up to 2,500/1,500 MB/s and 300K/110K random IOPS.

Samsung is the first SSD manufacturer to utilize 3D stacked NAND, which Samsung calls V-NAND. The benefits of V-NAND over traditional planar NAND is that stacking (32 layers in the current V-NAND) allows for more capacity in the same physical area, with only slightly increased volume—the layers are quite thin. Where this becomes useful is when using an older manufacturing process, 40nm in the case of current V-NAND. Competing NAND solutions are now using processes as small as 15nm, but unlike CPUs and GPUs, for NAND smaller isn’t always better—in fact, in many ways it’s worse. Smaller transistors mean less ability to store charges in the NAND cells, with the result being that each NAND cell has fewer program/erase cycles before it stops working. By winding back the clock to 40nm, Samsung’s V-NAND offers a great balance of performance and capacity.

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Best NVMe SSD for Desktops

  • Fastest NVMe SSD
  • Highest capacity consumer NVMe SSD
  • Works in any x4 PCIe slot
  • No throttling
  • Uses a PCIe slot
  • Not for laptops

M.2 is great for laptops and newer systems, but what if you’re using a desktop? Assuming you have a spare PCIe slot (at least a physical x4 connector), there are other drives available. In fact, Intel’s SSD 750 SSDs were the first consumer NVMe drives to hit the market, and in many respects they’re still the fastest drives around. And unlike the Samsung 950 Pro, you can get far more capacity than 512GB—1.2TB to be precise. For desktop users, our go-to NVMe SSD remains Intel’s SSD 750 1.2TB monster.

Built from the same DNA as the company’s enterprise DC P3700, the SSD 750 is a consumer-focused drive with firmware optimizations that favor improved random I/O rather than maximum peak transfer rates. In practice, this yields better overall performance in some cases compared to the 950 Pro, but there are other instances where Samsung wins out. Peak performance is rated at 2,500/1,200 MB/s read/write, with a whopping 460K/290K IOPS; for random write I/O, it’s hard to beat the SSD 750. The lower-capacity 400GB SSD 750 doesn’t perform quite as well as the 1.2TB model, and there’s also an 800GB model now, but if you’re serious about NVMe storage we would stick with the 1.2TB drive. For those with the appropriate system, Intel offers the SSD 750 in a 2.5-inch form factor, using a U.2 (previously SFF-8639) connector. Those are as rare as hen’s teeth, particularly for consumer motherboards; while it’s possible to get an M.2 to U.2 adapter, in practice we’d stick with the PCIe add-in card models.

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Best Entry-Level NVMe SSD

  • Costs under $200
  • Still very fast
  • Works well in laptops
  • Higher price per GB
  • Low-ish capacity
  • Not as fast as 512GB model

Is there really such a thing as an “entry-level” NVMe SSD? Frankly, no, there’s not—the least expensive drive is the little brother of our primary choice, the Samsung 950 Pro 256GB. You have to give up half the capacity in the process, but for less-demanding users 256GB may still be sufficient. Due to the decreased parallelism, this model is also going to be a bit slower in peak performance compared to the 512GB drive. It’s rated at 2,200/900 MB/s read/write, with 270K/85K IOPS. The good news is that it’s still extremely fast, and it also costs less than $200 ($190 at the time of writing).

You can read our full review of the drive, but most of what we said about the 512GB drive applies here. Rather than focus on detailing the minor differences between the 256GB and 512GB models, let’s talk about a few of the other NVMe SSDs that we eliminated from the list and explain why they didn’t make the cut.

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An Eye Toward the Future

That takes care of the recommendations for existing NVMe SSDs, but as we mentioned above, there are many products slated to ship in the coming months. We previewed most of these at CES 2016, and with more consumer NVMe drives coming out, we're hoping to see more competition on pricing. Remember that the NAND chips make up a substantial portion of the total SSD price, and fundamentally there usually isn’t much of a difference between, for example, a SATA drive with 512GB V-NAND and an M.2 NVMe drive with the same 512GB V-NAND. NVMe requires a new controller and firmware, of course, and there are associated R&D costs, but long-term NVMe prices should dovetail SATA SSD prices, with a moderate premium. Economies of scale are still a factor, naturally, so until more systems use NVMe SSDs, prices will stay higher. And we’re still waiting with baited breath for more details on 3D XPoint Technology, but let’s get to the drives we know about.

First up, Patriot announced their Hellfire SSDs, scheduled to ship in the March time frame. These will use the new Phison 5007 controller, and while traditionally Phison hasn’t offered top performance, they’ve improved over the years, so it will be interesting to test the Hellfire. The Hellfire will come in two forms, M.2 and add-in card (AIC), with capacities of 240GB/480GB/960GB. It will use MLC NAND, with performance rated at up to 3,000/2,200 MB/s read/write. Whether it can sustain those values remains to be seen. Zotac has a similar-looking AIC NVMe drive coming, also using the Phison 5007 controller, with speeds rated at up to 2,500/1,200 MB/s, and it should be available later this month or early next. Planned capacities and pricing were not revealed.

OCZ has been a long-time player in the PCIe AIC SSD market, going back to their original RevoDrive in 2010. At CES, they announced their new RevoDrive 400, an M.2 solution with capacities up to 1TB. OCZ didn’t provide any details on the controller or pricing, but did state that the RevoDrive 400 will offer read/write speeds up to 2,400/1,600 MB/s. Given those specs, it’s entirely possible the RevoDrive 400 will use the same Phison 5007 controller as the Patriot and Zotac drive—not to mention OCZ/Toshiba have used Phison controllers in several other drives of late.

Next, Kingston has an NVMe version of their HyperX Predator slated to launch this year. The non-NVMe Predator didn’t set our pants on fire, but the new drive was posting read/write speeds of 2,585/1,354MB/s at the Kingston CES booth. The company hasn’t provide too many details yet, other than planned capacities of 240/480/960GB. Like the current Predator, it will be an M.2 form factor drive, though a PCIe AIC adapter will also be available. Unfortunately, there was no word on pricing, launch date, IOPS performance, or controller provided. Even less is known about Plextor’s M8Pe, other than that it will be offered in an AIC format and features a PCIe x4 Gen3 interface. It’s rated at up to 270K/150K read/write IOPS, which is similar to Samsung’s 950 Pro, but we’ll have to wait for more details.

The good news is that with no fewer than five new consumer NVMe SSDs set to launch in the coming months, competition in this market is about to become a lot more interesting. As we separate the contenders from the pretenders over the coming months, we expect to see prices decrease on NVMe drives while performance continues to increase. Some of these drives are getting close to saturating even a PCIe x4 Gen3 link, which is awesome to think about. In practice, of course, many of these drives are pushing the storage bottleneck so far north that other components in your PC will become the limiting factor.

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