fantastic SSD that can’t be found / Storage

“The market has decided” is a phrase quite often heard from skeptics who believe that free competition in the absence of regulation inevitably leads to a deterioration in the quality of goods due to the desire of manufacturers to infinitely reduce production costs. This is certainly possible, but in the segment of inexpensive SSD with interface PCIe 4.0 events are developing in a completely different direction – here the market has directed progress in favor of consumers. Indeed, leading manufacturers have almost completely abandoned the use of QLC memory in such drives and are now reducing their cost not due to slow flash memory with a low resource, but by using four-channel controllers and introducing HMB technology instead of adding buffer SDRAM memory to drives.

Initially, this design also did not seem like a good option – until recently, bufferless NVMe drives did not look particularly attractive, offering obviously lower performance compared to their full-fledged counterparts. The only relatively bright spot in this segment was perhaps Samsung 980, but even he could not compete with mid-range drives even produced by second- or third-tier companies, not to mention more thoroughbred products. But progress does not stand still, and more recently, market competition has given birth to the Innogrit IG5220 bufferless platform – a high-end budget solution. The first drive based on it that came to our laboratory, Patriot P400made a real sensation: as it turned out, the bufferless SSD has ceased to be a sentence, and in real workloads they are quite capable of offering performance close to the flagship.

It is even more pleasant that the appearance of the Patriot P400 stirred up other manufacturers, who also began to produce similar or even better solutions in terms of consumer characteristics. So, quite recently, a no less attractive novelty appeared at Western Digital. Despite the fact that at the end of last year it already released a bufferless PCI 4.0 drive WD Black SN750 SE based on the publicly available Phison E19T platform, now it has been replaced by a new, reinforced model on all fronts – the WD Black SN770. And this is a direct result of the work of market mechanisms.

The WD Black SN750 SE obviously couldn’t compete with solutions like the Patriot P400, and Western Digital had to urgently redraw the lineup. And this time the company decided not to step on the same rake a second time and instead of choosing another public platform for an inexpensive PCIe 4.0 SSD, they made their own, which should be even better. That’s how the new hero, the WD Black SN770, was born, which, while inspired by the Innogrit IG5220 platform, is made from start to finish by SanDisk’s in-house engineering team.

Judging by the passport figures, the WD Black SN770 offers about one and a half times better performance compared to the Black SN750 SE and falls into the same league with Crucial P5 Plus, despite the fact that we are talking about a simple bufferless model. At the same time, the recommended price of the Black SN770 is on the same level with the price of the Black SN750 SE and almost does not differ from the recommended price of the Samsung 980, which causes great interest in the new product. And although Western Digital drives have ceased to be delivered to Russia through the official channel, there is hope that the Black SN770 will still reach domestic retail under the parallel import scheme. To prepare for this moment, we comprehensive testing of this SSD.

See also  A concerto for everyone | The standard

#Appearance and internal arrangement

WD Black SN770 is designed as a single-sided M.2 2280 board with black textolite and without any pre-installed cooling means. One could say that it looks like a typical budget SSD, but there is one peculiarity – all its stuffing is densely packed in just two microcircuits.

One chip is a SanDisk proprietary controller marked 20-82-10081-A1. Western Digital does not disclose details about its developments, however, it is known that this chip is built on the same functional blocks as the 20-82-10034-A1 controller, which is used in the flagship WD Black SN850. But in this case, it is significantly simplified: the DRAM interface is removed from it, instead of which support for HMB technology is added, and the number of flash memory channels is also reduced – up to four. However, there is also good news. Firstly, the WD Black SN770 controller still has full support for four PCIe 4.0 lanes. Secondly, it received compatibility with modern and fast 112-layer BiCS5 memory with an interface frequency of 1.2 GHz, which Western Digital has been producing since the beginning of last year.

Actually, the second chip on the WD Black SN770 just carries SanDisk BiCS5 memory chips. In this case, these are 512-Gb TLC 3D NAND devices in an amount corresponding to the capacity of the drive. As part of this review, we are considering a terabyte, and in it the flash memory array is assembled from 16 crystals, when accessed by a four-channel controller, it uses four interleaving.

Last time we saw BiCS5 memory in the WD Blue SN570, but there this memory could not prove itself due to the weakness of the controller. In the WD Black SN770, it should show its qualities more clearly – the 112-layer design of TLC 3D NAND chips promises not only a 40 percent improvement in density compared to BiCS4, but also a 50 percent improvement in performance.

The minimalist design of the WD Black SN770 can be traced not only in the minimum number of chips. Its signs are also in the label – in this case, it is half the usual size and does not cover the SSD components. However, the content did not suffer much. It fit not only the name, model number and capacity of the drive, but also the serial number, as well as the production date. Two QR codes, which take up a fairly large area on the sticker, duplicate the serial number and PSID, which in this case is unlikely to ever be needed, since hardware encryption does not work in the WD Black SN770.

See also  VMware Fusion Preview Release, Supports Windows 11 with Emulator on Mac

Western Digital traditionally uses “color differentiation” to categorize products by performance and intended use cases. The Black series was originally intended to be a high-end enthusiast- and gamer-oriented model, and it’s rather strange to see a minimalist drive without a DRAM buffer in this series. But it seems that Western Digital believes that storing the address translation table in the main memory of a PC, provided that the PCIe 4.0 x4 interface is used, does not undermine real performance too much, so the WD Black SN770 can be included in the same subgroup with the flagship Black SN850. However, HMB technology still cannot fully replace the dedicated DRAM buffer, if only because operating systems are ready to give no more than 64 MB of memory for SSD needs. But at the same time, the WD Black SN770 is clearly better than those available in the company’s Blue mass series of SSDs – it includes devices with simpler interfaces: PCIe 3.0 and SATA.


Like the previously reviewed Patriot P400 based on the Innogrit IG5220, the WD Black SN770 promises linear operation speeds of 5 GB/s. At the same time, the performance of small-block reads and writes also looks quite decent – according to these characteristics, the new Western Digital is comparable to drives based on the eight-channel Phison E16 controller. In other words, the specifications of the Black SN770 look promising.

Manufacturer Western Digital
Series WD Blue SN770
Model number WDS250G3X0E WDS500G3X0E WDS100T3X0E WDS200T3X0E
Form factor M.2 2280
Interface PCI Express 4.0 x4 – NVMe 1.4
Capacity 250 GB 500 GB 1000 GB 2000 GB
Flash memory: type, manufacturing process, manufacturer SanDisk 112-layer 512Gb TLC 3D NAND (BiCS5)
Controller SanDisk 20-82-01081-A1
Buffer: type, volume Not
Max. sustained sequential read speed, MB/s 4000 5000 5150 5150
Max. sustained sequential write speed, MB/s 2000 4000 4900 4850
Max. random read speed (blocks of 4 KB), IOPS 240 thousand. 460 thousand. 740 thousand. 650 thousand.
Max. random write speed (blocks of 4 KB), IOPS 470 thousand. 800 thousand. 800 thousand. 800 thousand.
physical characteristics
Max. power consumption, W N/A
MTBF (mean time between failures), mln h N/A
Resource Record, Tbytes 200 300 600 1200
Warranty period, years 5
Dimensions: L × H × G, mm 80 × 22 × 2,38
See also  Gazprom announces 'large-scale filling' of five gas storage facilities in Europe

The WD Black SN770 is available in four capacities from 250 GB to 2 TB. The fastest version is terabyte, which is the one that appears in our testing. At the same time, the 2TB version is not far behind it. But smaller-capacity drives are already losing performance more noticeably, since they have a lower degree of parallelism of the flash memory array.

The CrystalDiskMark test, which we run to check the speeds declared by the manufacturer, confirms: the WD Black SN770 is an absolutely atypical bufferless SSD, which is one of the best representatives of this class. It really gives out the characteristics indicated in the specification, despite the four-channel flash memory array and the lack of a controller buffer.

Moreover, thanks to the use of BiCS5 memory, this SSD shows very good speed in non-pipelined 4-KB read operations and does not succumb to mixed loads, which the repeatedly mentioned Patriot P400 does not do very well. In sum, all this means only one thing: the WD Black SN770 is a clear contender for the role of the best inexpensive SSD with PCIe 4.0 interface.

The advantages of the drive under consideration include a five-year warranty with quite typical conditions for flagship models, allowing 600-fold overwriting of the full capacity during its lifetime. But the WD Black SN770 becomes even more attractive when you find out about its price. The recommended cost of the terabyte version is only $110, that is, this SSD is positioned as a direct competitor to the Samsung 980, while promising both PCIe 4.0 support and significantly higher performance.


For its drives, Western Digital has developed and is developing the WD SSD Dashboard service utility, and this is one of the best programs of this kind. It has a clear and pleasant interface and is packed with all the necessary features. With its help, you can monitor the status, performance and health of the drive, update its firmware and perform maintenance operations on the flash memory array.

And it also has a special switch to activate the “game” mode, which turns off the power-saving functions and due to this, the reaction time is reduced. However, this possibility should not be overestimated – it is more of an ideological nature, supporting the gaming role of the WD Black SN770, but not having a noticeable effect on real performance.

In addition to the WD SSD Dashboard, a special branded version of Acronis True Image software is also available for the drive in question, with which you can clone data and transfer partitions from one storage medium to another.

If you notice an error, select it with the mouse and press CTRL+ENTER.

Leave a Comment

This site uses Akismet to reduce spam. Learn how your comment data is processed.