Western Digital has a long and rich history in the storage market, but for a long time it wasn’t a player in the consumer solid-state storage space. The company first started to dabble in SSDs with its acquisition of Siliconsystems almost ten years ago, but that was a ticket into the business-focused market only. It wasn’t until the company’s much more recent and more expensive purchase of SanDisk that WD became truly ready to enter the mainstream SSD fray.
Freshly armed with SanDisk’s existing client SSD portfolio and the technologies and foundries of the SanDisk-Toshiba joint venture, WD wasted little time in getting SSDs carrying its own brand out the door. Its initial salvo was an unassuming set of re-badged SanDisk SATA drives, but the firm followed up with something more interesting: the Black PCIe SSD. The Black was an NVMe M.2 gumstick marketed as a lower-cost alternative to faster and more established NVMe product lines.
This year, however, Western Digital issued a new iteration of the Black SSD with a markedly different goal. Meet the WD Black NVMe SSD.
|WD Black NVMe SSD|
|Capacity||Max sequential (MB/s)||Max random (IOps)|
The naming scheme may not be crystal clear, so let’s break it down. The older Black is 2017’s “Black PCIe SSD.” It came in 256-GB and 512-GB capacities and was intended to be a low-cost entry point into NVMe PCIe drives. This year’s Black drive is the “Black NVMe SSD.” It comes in 250-GB, 500-GB, and 1-TB versions. WD touts the new drive as a high-performance player, unlike its more humble predecessor. The 1-TB version boasts particularly lofty performance numbers. That’s the one WD sent us to play with, so we’ll gladly put them to the test. As an aside, Western Digital will also be selling this exact drive under the SanDisk brand as the Extreme Pro M.2 NVMe 3D SSD, but only in the 500-GB and 1-TB capacities.
So what’s changed in a year? A lot. The 2017 drive’s blue PCB has been replaced with a more namesake-appropriate black one. Beneath the sticker are more significant changes. Marvell’s 88SS1093 controller has been booted out in favor of a new in-house design: a SanDisk-branded controller sandwiched in between the memory packages. The controller features the latest version of SanDisk’s proprietary nCache 3.0 pseudo-SLC caching scheme. Additionally, the controller is capable of bypassing nCache to write directly to TLC when the caches are too busy to service incoming writes.
The drive’s NAND is the same goodness we reviewed in Toshiba’s XG5 OEM SSD, but this time the cells are bundled up in packages bearing SanDisk’s name. We were very taken with the XG5 when we tested it and are still impatient for a retail version of the drive. Maybe the Black NVMe can scratch the itch in the meantime.
Western Digital warrants the Black drives for five years and rates the 1 TB version’s endurance at 600 terabytes written, matching the guarantees of the 970 EVO 1 TB that WD is so clearly gunning for.
The Black also matches the 970 EVO’s price. The WD Black NVMe is available at Newegg for $400 even. Despite carrying the same tag as Samsung’s latest, the Black unfortunately provides no hardware encryption acceleration features. But if the performance is good enough, we may be willing to relax our privacy principles. Let’s see what Western Digital’s new halo drive can do.
IOMeter — Sequential and random performance
IOMeter fuels much of our latest storage test suite, including our sequential and random I/O tests. These tests are run across the full capacity of the drive at two queue depths. The QD1 tests simulate a single thread, while the QD4 results emulate a more demanding desktop workload. For perspective, 87% of the requests in our old DriveBench 2.0 trace of real-world desktop activity have a queue depth of four or less. Clicking the buttons below the graphs switches between results charted at the different queue depths.
Our sequential tests use a relatively large 128-KB block size.
The WD Black languishes at QD1 with sequential reads. That’s not a good place to languish, since it represents performance typical for PC users. Otherwise, it seems to keep up with the 970 EVO 1 TB. The XG5 is faster across the board, so perhaps WD still has a thing or two to learn from the older SSD players about controller optimization. Random reads and writes come next.
Respectable. The WD drive is very responsive, especially with its random writes.
The WD Black is doing fine in our first round of synthetics, but has yet to set itself apart from the NVMe pack. There are plenty of benchmarks to go, so it still has time to prove itself. Let’s move on to sustained and scaling tests.
Sustained and scaling I/O rates
Our sustained IOMeter test hammers drives with 4KB random writes for 30 minutes straight. It uses a queue depth of 32, a setting that should result in higher speeds that saturate each drive’s overprovisioned area more quickly. This lengthy—and heavy—workload isn’t indicative of typical PC use, but it provides a sense of how the drives react when they’re pushed to the brink.
We’re reporting IOPS rather than response times for these tests. Click the buttons below the graph to switch between SSDs.
Yikes. Peak and steady-state both look pretty rough for a drive of this caliber. Let’s see what the numbers are.
The WD Black NVMe’s peak rate is half that of the XG5 and only a third that of the 970 EVO 1 TB. Steady-state performance isn’t quite as rough, but it’s still less than you want from a drive like this. We’ve reached out to Western Digital for comment, but this is likely yet another instance of a drive’s firmware and caching algorithms needing more time to recover from IOMeter test setup than our process gives.
Our final IOMeter test examines performance scaling across a broad range of queue depths. We ramp all the way up to a queue depth of 128. Don’t expect AHCI-based drives to scale past 32, though—that’s the maximum depth of their native command queues.
For this test, we use a database access pattern comprising 66% reads and 33% writes, all of which are random. The test runs after 30 minutes of continuous random writes that put the drives in a simulated used state. Click the buttons below the graph to switch between the different drives. And note that the P3700 plot uses a much larger scale.
Scaling is not the WD Black’s strong suit. Its best performance is at QD4, but beyond that its graphs are SATA-like flat ground.
As you can see, most other NVMe drives squeeze out more power until at least QD16. The WD Black just isn’t interested. To be fair, most consumer workloads aren’t nearly that parallel, and the Black remains quite competitive in the lower queue depths that client users should be interested in.
Our IOMeter synthetics proved a rough patch for Western Digital’s new gumstick. But we’re exiting the quagmire of IOMeter for the greener pastures of real-world tests. Maybe RoboBench will be the Black’s cup of tea.
TR RoboBench — Real-world transfers
RoboBench trades synthetic tests with random data for real-world transfers with a range of file types. Developed by our in-house coder, Bruno “morphine” Ferreira, this benchmark relies on the multi-threaded robocopy command build into Windows. We copy files to and from a wicked-fast RAM disk to measure read and write performance. We also cut the RAM disk out of the loop for a copy test that transfers the files to a different location on the SSD.
Robocopy uses eight threads by default, and we’ve also run it with a single thread. Our results are split between two file sets, whose vital statistics are detailed below. The compressibility percentage is based on the size of the file set after it’s been crunched by 7-Zip.
|Number of files||Average file size||Total size||Compressibility|
RoboBench’s write and copy tests run after the drives have been put into a simulated used state with 30 minutes of 4KB random writes. The pre-conditioning process is scripted, as is the rest of the test, ensuring that drives have the same amount of time to recover.
The media set is made up of large movie files, high-bitrate MP3s, and 18-megapixel RAW and JPG images. There are only a few hundred files in total, and the data set isn’t amenable to compression. The work set comprises loads of TR files, including documents, spreadsheets, and web-optimized images. It also includes a stack of programming-related files associated with our old Mozilla compiling test and the Visual Studio test on the next page. The average file size is measured in kilobytes rather than megabytes, and the files are mostly compressible.
Let’s take a look at the media set first. The buttons switch between read, write, and copy results.
The WD Black NVMe’s performance in the media set is nothing short of spectacular, a far cry from the doldrums of IOMeter. The Black claims a record speeds in the 1T write test as well as both copy tests. In fact, its copy results were so good I was forced to change the axis scale from previous reviews.
Next, the work set.
Our work set is typically a great equalizer. The WD Black still puts up great numbers, but it’s not so dominant as it is in the media set. Nonetheless, it snags new records in the 8T write and copy tests.
In the span of a single page of tests, the WD Black NVMe went from unremarkable to record-setting. This is why we can’t rely purely on synthetics. Our last page of tests will see how the Black fares with boot duties.
Until now, all of our tests have been conducted with the SSDs connected as secondary storage. This next batch uses them as system drives.
We’ll start with boot times measured two ways. The bare test depicts the time between hitting the power button and reaching the Windows desktop, while the loaded test adds the time needed to load four applications—Avidemux, LibreOffice, GIMP, and Visual Studio Express—automatically from the startup folder. Our old boot tests focused on the time required to load the OS, but these new ones cover the entire process, including drive initialization.
The Black’s boot times land very near the top of the charts. No complaints.
Next, we’ll tackle load times with two sets of tests. The first group focuses on the time required to load larger files in a collection of desktop applications. We open a 790-MB 4K video in Avidemux, a 30-MB spreadsheet in LibreOffice, and a 523-MB image file in the GIMP. In the Visual Studio Express test, we open a 159-MB project containing source code for the LLVM toolchain. Thanks to Rui Figueira for providing the project code.
Nothing out of the ordinary. The WD Black’s application load times are typical.
Games also load up as snappily as can be expected.
Like every other SSD in our test set, the WD Black NVMe blends into the crowd when it comes to boot and load times. Now we’re out of tests, so read on for test methods or skip a page to go straight to the conclusion.
Test notes and methods
Here are the essential details for all the drives we tested:
|Adata Premier SP550 480GB||SATA 6Gbps||Silicon Motion SM2256||16-nm SK Hynix TLC|
|Adata Ultimate SU800 512GB||SATA 6Gbps||Silicon Motion SM2258||32-layer Micron 3D TLC|
|Adata Ultimate SU900 256GB||SATA 6Gbps||Silicon Motion SM2258||Micron 3D MLC|
|Adata XPG SX8200 480GB||PCIe Gen3 x4||Silicon Motion SM2262||64-layer Micron 3D TLC|
|Adata XPG SX930 240GB||SATA 6Gbps||JMicron JMF670H||16-nm Micron MLC|
|Corsair MP500 240GB||PCIe Gen3 x4||Phison 5007-E7||15-nm Toshiba MLC|
|Crucial BX100 500GB||SATA 6Gbps||Silicon Motion SM2246EN||16-nm Micron MLC|
|Crucial BX200 480GB||SATA 6Gbps||Silicon Motion SM2256||16-nm Micron TLC|
|Crucial MX200 500GB||SATA 6Gbps||Marvell 88SS9189||16-nm Micron MLC|
|Crucial MX300 750GB||SATA 6Gbps||Marvell 88SS1074||32-layer Micron 3D TLC|
|Crucial MX500 500GB||SATA 6Gbps||Silicon Motion SM2258||64-layer Micron 3D TLC|
|Crucial MX500 1TB||SATA 6Gbps||Silicon Motion SM2258||64-layer Micron 3D TLC|
|Intel X25-M G2 160GB||SATA 3Gbps||Intel PC29AS21BA0||34-nm Intel MLC|
|Intel 335 Series 240GB||SATA 6Gbps||SandForce SF-2281||20-nm Intel MLC|
|Intel 730 Series 480GB||SATA 6Gbps||Intel PC29AS21CA0||20-nm Intel MLC|
|Intel 750 Series 1.2TB||PCIe Gen3 x4||Intel CH29AE41AB0||20-nm Intel MLC|
|Intel DC P3700 800GB||PCIe Gen3 x4||Intel CH29AE41AB0||20-nm Intel MLC|
|Mushkin Reactor 1TB||SATA 6Gbps||Silicon Motion SM2246EN||16-nm Micron MLC|
|OCZ Arc 100 240GB||SATA 6Gbps||Indilinx Barefoot 3 M10||A19-nm Toshiba MLC|
|OCZ Trion 100 480GB||SATA 6Gbps||Toshiba TC58||A19-nm Toshiba TLC|
|OCZ Trion 150 480GB||SATA 6Gbps||Toshiba TC58||15-nm Toshiba TLC|
|OCZ Vector 180 240GB||SATA 6Gbps||Indilinx Barefoot 3 M10||A19-nm Toshiba MLC|
|OCZ Vector 180 960GB||SATA 6Gbps||Indilinx Barefoot 3 M10||A19-nm Toshiba MLC|
|Patriot Hellfire 480GB||PCIe Gen3 x4||Phison 5007-E7||15-nm Toshiba MLC|
|Plextor M6e 256GB||PCIe Gen2 x2||Marvell 88SS9183||19-nm Toshiba MLC|
|Samsung 850 EV0 250GB||SATA 6Gbps||Samsung MGX||32-layer Samsung TLC|
|Samsung 850 EV0 1TB||SATA 6Gbps||Samsung MEX||32-layer Samsung TLC|
|Samsung 850 Pro 512GB||SATA 6Gbps||Samsung MEX||32-layer Samsung MLC|
|Samsung 860 Pro 1TB||SATA 6Gbps||Samsung MJX||64-layer Samsung MLC|
|Samsung 950 Pro 512GB||PCIe Gen3 x4||Samsung UBX||32-layer Samsung MLC|
|Samsung 960 EVO 250GB||PCIe Gen3 x4||Samsung Polaris||32-layer Samsung TLC|
|Samsung 960 EVO 1TB||PCIe Gen3 x4||Samsung Polaris||48-layer Samsung TLC|
|Samsung 960 Pro 2TB||PCIe Gen3 x4||Samsung Polaris||48-layer Samsung MLC|
|Samsung 970 EVO 1TB||PCIe Gen3 x4||Samsung Phoenix||64-layer Samsung TLC|
|Samsung SM951 512GB||PCIe Gen3 x4||Samsung S4LN058A01X01||16-nm Samsung MLC|
|Samsung XP941 256GB||PCIe Gen2 x4||Samsung S4LN053X01||19-nm Samsung MLC|
|Toshiba OCZ RD400 512GB||PCIe Gen3 x4||Toshiba TC58||15-nm Toshiba MLC|
|Toshiba OCZ VX500 512GB||SATA 6Gbps||Toshiba TC358790XBG||15-nm Toshiba MLC|
|Toshiba TR200 480GB||SATA 6Gbps||Toshiba TC58||64-layer Toshiba BiCS TLC|
|Toshiba XG5 1TB||PCIe Gen3 x4||Toshiba TC58||64-layer Toshiba BiCS TLC|
|Transcend SSD370 256GB||SATA 6Gbps||Transcend TS6500||Micron or SanDisk MLC|
|Transcend SSD370 1TB||SATA 6Gbps||Transcend TS6500||Micron or SanDisk MLC|
|Western Digital Black NVMe 1TB||PCIe Gen3 x4||64-layer SanDisk BiCS TLC|
All the SATA SSDs were connected to the motherboard’s Z97 chipset. The M6e was connected to the Z97 via the motherboard’s M.2 slot, which is how we’d expect most folks to run that drive. Since the XP941, 950 Pro, RD400, and 960 Pro require more lanes, they were connected to the CPU via a PCIe adapter card. The 750 Series and DC P3700 were hooked up to the CPU via the same full-sized PCIe slot.
We used the following system for testing:
|Processor||Intel Core i5-4690K 3.5GHz|
|Platform hub||Intel Z97|
|Platform drivers||Chipset: 10.0.0.13
|Memory size||16GB (2 DIMMs)|
|Memory type||Adata XPG V3 DDR3 at 1600 MT/s|
|Audio||Realtek ALC1150 with 220.127.116.1144 drivers|
|System drive||Corsair Force LS 240GB with S8FM07.9 firmware|
|Storage||Crucial BX100 500GB with MU01 firmware
Crucial BX200 480GB with MU01.4 firmware
Crucial MX200 500GB with MU01 firmware
Intel 335 Series 240GB with 335u firmware
Intel 730 Series 480GB with L2010400 firmware
Intel 750 Series 1.2GB with 8EV10171 firmware
Intel DC P3700 800GB with 8DV10043 firmware
Intel X25-M G2 160GB with 8820 firmware
Plextor M6e 256GB with 1.04 firmware
OCZ Trion 100 480GB with 11.2 firmware
OCZ Trion 150 480GB with 12.2 firmware
OCZ Vector 180 240GB with 1.0 firmware
OCZ Vector 180 960GB with 1.0 firmware
Samsung 850 EVO 250GB with EMT01B6Q firmware
Samsung 850 EVO 1TB with EMT01B6Q firmware
Samsung 850 Pro 500GB with EMXM01B6Q firmware
Samsung 950 Pro 512GB with 1B0QBXX7 firmware
Samsung XP941 256GB with UXM6501Q firmware
Transcend SSD370 256GB with O0918B firmware
Transcend SSD370 1TB with O0919A firmware
|Power supply||Corsair AX650 650W|
|Case||Fractal Design Define R5|
|Operating system||Windows 8.1 Pro x64|
Thanks to Asus for providing the systems’ motherboards, to Intel for the CPUs, to Adata for the memory, to Fractal Design for the cases, and to Corsair for the system drives and PSUs. And thanks to the drive makers for supplying the rest of the SSDs.
We used the following versions of our test applications:
- IOMeter 1.1.0 x64
- TR RoboBench 0.2a
- Avidemux 2.6.8 x64
- LibreOffice 4.3.2
- GIMP 2.8.14
- Visual Studio Express 2013
- Batman: Arkham Origins
- Tomb Raider
- Middle Earth: Shadow of Mordor
Some further notes on our test methods:
- To ensure consistent and repeatable results, the SSDs were secure-erased before every component of our test suite. For the IOMeter database, RoboBench write, and RoboBench copy tests, the drives were put in a simulated used state that better exposes long-term performance characteristics. Those tests are all scripted, ensuring an even playing field that gives the drives the same amount of time to recover from the initial used state.
- We run virtually all our tests three times and report the median of the results. Our sustained IOMeter test is run a second time to verify the results of the first test and additional times only if necessary. The sustained test runs for 30 minutes continuously, so it already samples performance over a long period.
- Steps have been taken to ensure the CPU’s power-saving features don’t taint any of our results. All of the CPU’s low-power states have been disabled, effectively pegging the frequency at 3.5GHz. Transitioning between power states can affect the performance of storage benchmarks, especially when dealing with short burst transfers.
The test systems’ Windows desktop was set at 1920×1080 at 60Hz. Most of the tests and methods we employed are publicly available and reproducible. If you have questions about our methods, hit our forums to talk with us about them.
The WD Black NVMe suffered an asthmatic performance in IOMeter, but its RoboBench performance was phenomenal. Western Digital had its sights set on the 970 EVO, and we expect that the Black’s overall performance will fall fairly close to its rival. We distill the overall performance rating using an older SATA SSD as a baseline. To compare each drive, we then take the geometric mean of a basket of results from our test suite. Only drives which have been through the entire current test suite on our current rig are represented.
Close, but a little short. The 970 EVO suffered its own share of setbacks in IOMeter versus its faultless predecessor, but the WD Black’s shortcomings weighed it down a bit more heavily in the overall rankings. Nonetheless, this is an impressive showing from Western Digital. Samsung is the top dog in this market, and WD has wasted no time in wielding its newly-acquired solid-state prowess to build a platform that can challenge the 800-lb gorilla’s traditional technology advantage.
But does this have any meaning for us small-time hobbyist builders? We have to examine the value proposition first. In the plots below, the most compelling position is toward the upper left corner, where the price per gigabyte is low and performance is high. Use the buttons to switch between views of all drives, only SATA drives, or only PCIe drives.
Despite being announced at $450, the Black NVMe 1 TB is going for $400 at both Newegg and Western Digital’s own website. If Samsung and WD want to play a game of chicken with their prices, all the better for you and me. The $0.40 per gigabyte that the $400 tag represents exactly matches the cost of the 970 EVO 1 TB. That’s a fine price for the sort of performance that these drives deliver. That’s especially true since there’s a dearth of cheaper options in NVMe storage right now. Intel’s 760p 512 GB has a suggested price of $200 even, but street prices are currently hovering around $220. The only NVMe drive in our set currently cheaper than the WD Black or 970 EVO is the Adata SX8200 we just reviewed.
At the end of the day, the WD Black NVMe 1 TB and 970 EVO 1 TB both boast more than enough oomph for the typical enthusiast’s needs. Builders who need better encryption features will gravitate towards the Samsung, while others may value the WD’s absurd file transfer speeds. More than likely, it will come down which drive your favorite retailer is currently running a sale on. Western Digital has built a fine home for 64-layer BiCS 3D flash in its Black NVMe drive, and the company can proudly call the Black NVMe 1TB TR Recommended.