Western Digital WD_BLACK SN770 1TB NVMe Solid State Drive

Model: Western Digital WD_BLACK SN770 1TB NVMe Solid State Drive
Manufacturer: Western Digital
Provided By: Western Digital

As one of the biggest names in the storage industry, Western Digital doesn't need much of an introduction. Founded in 1970, the company got its start by manufacturing calculator chips. As time went on, Western Digital expanded into the PC market, adding floppy and hard disc controllers to its product lineup. It wasn't until 1988 that it introduced its "Centaur" series of hard drives. Since then, the company has grown to become the world's second largest manufacturer of hard drives. Western Digital currently offers a wide range of internal and external hard drives as well as a growing number of multimedia devices, SSDs and network storage solutions.

Earlier this year, Western Digital's unveiled the latest addition to its line of WD_BLACK NVMe SSDs, the SN770. Designed for use in PC gaming rigs, this compact, M.2 form factor SSD is powered by Western Digital's own 20-82-10081-A1 controller and is available with up to 2TB of the company's 112-layer BiCS5 3D TLC NAND flash. The WD_BLACK SN770 is also equipped with an PCIe Gen4 x4 interface to deliver ultra-fast read speeds of up to 5,150MB/s to fuel in-game responsiveness, minimize stutter, and provide smooth streaming for a performance boost that gamers can see and feel. Last, but not least, users can customize and control their gaming experience with the downloadable WD_BLACK Dashboard software.

The WD_BLACK SN770 is available in 250GB, 500GB, 1TB and 2TB capacities. For this review, Western Digital sent us the 1TB version of the drive, which is capable of delivering up to 5,150 MB/s sequential read and 4,900 MB/s sequential write speeds as well as up to 740,000 random read and 800,000 random write IOPS.

Needless to say, this is only a taste of what the WD_BLACK SN770 has to offer. To give you an idea of what to expect, we'll take a closer look at Western Digital's new PCIe 4.0 SSD and then see how well it performs. Does the WD_BLACK SN770 have what it takes? Can it deliver the performance and features that we've come to expect from Western Digital? Keep reading as we find out.

The WD_BLACK SN770 comes in a small, black box. Along with a picture of the drive, the front advertises a few of its key features including its 1TB capacity, Gen4 interface and maximum read speed. The back of the box also has a small window that lets you see the drive and view the model name and serial number.

Physical Features:

The WD_BLACK SN770 uses the 2280 form factor for M.2 (NGFF) SSDs. It measures 22 x 80 x 2.38 mm and tips the scales at a mere 5.5g. The drive also has an "M key" edge connector which provides PCIe SSDs with up to 4x lanes of bandwidth.

The WD_BLACK SN770 uses Western Digital's new SanDisk 20-82-10081-A1 controller. Not much is known about this controller aside from that it was designed in house, has four channels and is DRAM-less.

For the 1TB version of the WD_BLACK SN770, Western Digital has opted to use its own BiCS5 112-Layer TLC NAND flash. Looking at the picture above, you can see that there is a single 1TB NAND flash package on the top of the PCB. There is also no DRAM cache chip as the WD_BLACK SN770's controller takes full advantage of NVMe's Host Memory Buffer feature by using a small portion of the computer's memory to cache the mapping tables.

Like Western Digital's other SSDs, the WD_BLACK SN770 works with their WD_BLACK Dashboard software. This easy to use, Windows-based utility gives users the ability to manage and monitor their drives. From the main screen, you can check the status of your SSD and view information like the firmware version, capacity, temperature, interface speed and the life remaining.

With the WD_BLACK SN770, you can also enable what Western Digital calls "Gaming Mode." This feature disables the low power mode function on the SSD which keeps it running at peak levels.

The SSD Dashboard also gives users the ability to monitor the performance of their drives. The chart provides two different real time performance metrics: transfer speed MB/s (megabytes per second) and transfer IOPS (I/O operation count per second).

The Tools section offers a number of options, including the ability to do a firmware update and perform a secure erase. The SSD Dashboard also has the ability to run S.M.A.R.T. diagnostic tests and provide details about your drives and system.

From within the Settings tab, you can update SSD Dashboard and configure the software so that it starts up with Windows. You can also turn off write-cache buffer flushing and select from one of 17 languages.

Last, but not least, you have the Help section which contains links to Western Digital's support page as well as their end user forums.

The test system used in this review is equipped with an AMD Ryzen 5 3700x CPU, MSI B550 GAMING PLUS motherboard, 16GB (8GB x 2) of Crucial Ballistix 3200 MHz DDR4 memory, Crucial P5 1TB SSD and a GIGABYTE GeForce GTX 1060 WINDFORCE OC 6G graphics card. For the operating system, I used the latest version of Windows 10 Pro.

To test the performance of Western Digital's WD_BLACK SN770 SSD, I ran a series of benchmarks using CrystalDiskMark, HD Tach RW, ATTO Disk Benchmark, AS SSD, HD Tune Pro, Anvil's Storage Utilities, Iometer and PCMark. For comparison, I've also included test results from the ADATA XPG ATOM 50, ADATA XPG GAMMIX S70 Blade, Crucial P5 Plus, Plextor M10PY, ADATA XPG GAMMIX S70, Sabrent Rocket 4 Plus, WD_BLACK SN850, Silicon Power US70, ADATA XPG GAMMIX S50 Lite, Samsung 980, Silicon-Power UD70, Crucial P2, SK hynix Gold P31, Crucial P5, ADATA SWORDFISH, ADATA FALCON, Lexar NM610, Silicon Power P34A60, Patriot P300, Plextor M9PG Plus, Plextor M9PY Plus, ADATA XPG SX6000 Pro, Western Digital WD_BLACK SN750, Lexar NQ100, Samsung 970 EVO Plus, ADATA XPG SX8200 Pro, Crucial P1, ADATA XPG SX8200, Western Digital WD_BLACK NVMe, Samsung 970 EVO, Samsung 970 PRO, Plextor M9Pe, Plextor M8Se, Patriot Hellfire, ADATA XPG SX8000, Samsung 960 PRO, Toshiba OCZ RD400, Samsung 950 PRO, Samsung 870 EVO, Samsung 870 QVO, Silicon Power PC60 and SK hynix Gold S31.

As I mentioned earlier, the WD_BLACK SN770 uses Western Digital's new 20-82-10081-A1 controller chip.  Looking at the screenshot above, you can see that it performs equally well with both incompressible (0%) and compressible (100%) data.

CrystalDiskMark 8.0.4:

First, I ran a few quick tests using CrystalDiskMark. This benchmark measures the performance of a storage device by testing its sequential and random read and write speeds. For this test, we're using the peak and real world profiles.

According to Western Digital, the 1TB WD_BLACK SN770 is capable of reading at 5,150 MB/s and writing at 4,900 MB/s. As you can see, the drive had no problems reaching these speeds in CrystalDiskMark's sequential read and write tests.

As you'd expect, the WD_BLACK SN770 wasn't as fast when tested with the "real world" profile which uses a single thread and a much lower queue depth. Nevertheless, it was still able to read at 4,862 MB/s and write at more than 4,900 MB/s.

HD Tach RW 3.0.4.0:

Next, I used HD Tach to test the WD_BLACK SN770's read, write and burst speeds as well as its random access time and CPU usage.

Looking at the screenshot above, you can see that the WD_BLACK SN770 had average read and write speeds of 1373.6 MB/s and 1305.8 MB/s respectively, as well as a burst speed of 3006.2 MB/s. The screenshot also shows that it uses some sort of SLC caching. The drive starts writing at about 2,600 MB/s and then drops to about 600 MB/s when the write operation exceeds the size of the cache.

ATTO Disk Benchmark 4.01:

I also used ATTO Disk Benchmark to test the WD_BLACK SN770's sequential read and write speeds. The tests are run using blocks ranging in size from 512B to 64 MB and the total length set to 256MB.

WD_BLACK SN770 1TB

ADATA XPG ATOM 50 1TB

When tested with ATTO, the WD_BLACK SN770's read speeds topped out at about 4.61 GB/s and its write speeds at 4.90 GB/s.

AS SSD:

AS SSD is a benchmark designed specifically for solid state drives. The application contains five synthetic tests which are used to determine the sequential and random read and write performance of a drive.

WD_BLACK SN770 1TB

ADATA XPG ATOM 50 1TB

AS SSD also includes a copy benchmark. This test copies an ISO (two large files), program (many small files) and game (small and large files), returning the speed and duration of each.

WD_BLACK SN770 1TB

ADATA XPG ATOM 50 1TB

HD Tune Pro 5.75:

Next, I ran a series of tests using HD Tune Pro. This hard disk utility measures a drive's performance by testing its sequential read and write speeds as well as its access time, burst rate and CPU usage. For this review, I'm also going to use it to benchmark the WD_BLACK SN770's random read and write speeds, random access times and the number of operations per second.

WD_BLACK SN770 1TB - Read Benchmark

ADATA XPG ATOM 50 1TB - Read Benchmark

WD_BLACK SN770 1TB - Write Benchmark

ADATA XPG ATOM 50 1TB - Write Benchmark

The WD_BLACK SN770 performed relatively well when benchmarked with HD Tune. The drive had average read and write speeds of 4,324.7 MB/s and 2,091.4 MB/s, respectively.

WD_BLACK SN770 1TB - Random Access Read

ADATA XPG ATOM 50 1TB - Random Access Read

WD_BLACK SN770 1TB - Random Access Write

ADATA XPG ATOM 50 1TB - Random Access Write

When writing 4KB blocks, the WD_BLACK SN770 reached 50,233 IOPS and had an average speed of 196.225 MB/s. The drive was even faster when reading, reaching 54,942 IOPS with an average speed of 214.617 MB/s.

Anvil's Storage Utilities:

Anvil's Storage Utilities is another benchmark designed with SSDs in mind. The standard storage benchmark measures a drive's performance by testing its transfer speeds, access times and IOPS.

Iometer:

Lastly, I ran a series of tests using Iometer. This tool can be configured to benchmark a number of things. In this case, I used it to measure the WD_BLACK SN770's read and write speeds and the number of operations per second. The tests were run using random bytes and a queue depth of 3.

The WD_BLACK SN770's performance was very similar to what we saw in our other tests. The drive was able to read at 4877.51 MB/s and write at 4473.49 MB/s.

The WD_BLACK SN770 also performed fairly well when doing random reads and writes. In our tests, the drive was able to read at 362.96 MB/s and write at 641.50 MB/s.

According to ADATA, the 1TB WD_BLACK SN770 is capable of 740,000 IOPS when reading and 800,000 IOPS when writing 4K blocks. With two threads and a queue depth of three, the drive reached 92,917 random read IOPS and 164,224 random write IOPS.

As with most drives, the WD_BLACK SN770 performed better with more threads and at higher queue depths. With sixteen threads and the queue depth set to 32, it reached 507,792 random read IOPS and 578,987 random write IOPS. 

PCMark 8 - Storage Test:

PCMark 8 is a complete benchmark for Windows. It includes five benchmark tests, each designed around a specific scenario. The storage benchmark measures drive performance using real-world traces recorded from Adobe Creative Suite, Microsoft Office and a selection of popular games.

PCMark 8 also includes a consistency test which measures the performance consistency and degradation tendency of a storage system. The test reports the performance level at the start, the degraded steady-state and the recovered state as well as the number of iterations required to reach the degraded state and the recovered state. For this test, we are focusing on the Adobe Photoshop (Heavy) trace and will look at both the bandwidth and latency of the drive.

The WD_BLACK SN770's performance was hit and miss in this test. During the degradation and steady phases, the drive's bandwidth dropped below 200 MB/s, pushing its latency well above the 200ms mark. The WD_BLACK SN770 was able to recover though, jumping back up to 1048 MB/s.

PCMark 10 - Full System Drive Benchmark:

PCMark 10's Full System Drive Benchmark uses a wide-ranging set of real-world traces from popular applications and common tasks to fully test the performance of the fastest modern drives. This benchmark produces an overall score as a measure of drive performance. Comparing devices is as simple as comparing scores. The tests also measure and report the bandwidth and average access time performance for the drive.

The WD_BLACK SN770 did surprisingly well in PCMark 10's Full System Drive Benchmark. While not quite as fast as the Plextor M10PY or the WD_BLACK SN850, it performed better than the Crucial P5 Plus, ADATA XPG GAMMIX S70 Blade and Samsung 980 PRO.

TRIM Performance:

While SSDs offer many benefits, there are some downsides to using flash memory. One of the biggest issues people run into is performance degradation. Over time, an SSD will run out of fresh blocks and will have to write over data the file system has marked as deleted. This procedure is very complicated and can slow an SSD's write speeds considerably.

To fix this problem, most manufacturers have added TRIM support to their SSDs. The TRIM command allows an operating system, such as Windows 10, to tell an SSD which data blocks are no longer in use. Using this information, the drive pro-actively erases these blocks and adds them to the free block pool.

To test the WD_BLACK SN770's TRIM and garbage collection functions, I first put the drive in a "dirty" state. I used Iometer to fill 80% of the drive and then ran a random write test for 30 minutes. Looking at the screenshot below, you can see that the WD_BLACK SN770's average read and write speeds dropped to 3466.25 MB/s and 197.91 MB/s, respectively.

WD_BLACK SN770 - Dirty

To see how well the WD_BLACK SN770 could recover, I let the computer sit for about 30 minutes and then reran the test. The drive wasn't able to reach the factory fresh performance shown in our earlier tests. However, its sequential write speed climbed up to 4131.54 MB/s.

WD_BLACK SN770 - After TRIM

Lastly, I used Parted Magic to perform a secure erase on the WD_BLACK SN770. With the drive wiped clean, it had average read and write speeds of 4439.25 MB/s and 4316.28 MB/s, respectively.

 
WD_BLACK SN770- Secure Erased

Final Thoughts:

The WD_BLACK SN770 is an excellent choice for the gamer or enthusiast looking for a fast, yet affordable, PCIe 4.0 SSD for their desktop or notebook computer. Designed and built entirely in-house, this M.2 form factor SSD is powered by Western Digital's own 20-82-10081-A1 controller and is available with up to 2TB of the company's 112-layer BiCS5 3D TLC NAND flash. Combine this with a PCIe Gen4 x4 NVMe 1.4 interface and you have a drive that offers up to 40% faster performance than its predecessor, the SN750 SE. In our sequential read and write tests, the 1TB version of the WD_BLACK SN770 was able to read at speeds as high as 5,224 MB/s and write at speeds in excess of 4,900 MB/s. It also did fairly well in our random write tests, producing more than 164,000 IOPS at low queue depths, and scored better than many other, more expensive drives, in benchmarks like PC Mark 10.

The WD_BLACK SN770 is available now in 250GB, 500GB, 1TB and 2TB capacities. Prices on Amazon.com currently range from $53 up to $250, with the 1TB version reviewed here retailing for about $130.

Highs:

• Available in 250GB, 500GB, 1TB and 2TB capacities
• PCIe 4.0 x4 interface with NVMe protocol
• Equipped with 112-layer BiCS5 3D TLC NAND
• Very good sequential and random read and write speeds
• Small M.2 2280 form factor
• WD Black SSD Dashboard with "gaming mode"
• Reasonably priced
• 5 year warranty

Lows:

• Write speed drops considerably when SLC cache is full
• Does not support hardware based encryption