The American company WD is adjusting its mid-range SSD offer with the Black SN770. This series operates on a PCIe 4 interface and offers a maximum throughput of 5.15 GB/s. Enough to make it a playmate for Sony’s PS5 console.
The Black SN770 series represents the logical evolution of the SN750 series (M.2 PCIe 3). Renewed several times under the same name, this high-end series has since been reclassified to the rank of mid-range – an approach to be attributed to the arrival of the Black SN850s, which are faster and operate on a PCIe 4 interface.
The biggest change is obviously to be found on the side of the interface which is evolving towards PCIe 4 – a change which is becoming widespread among all manufacturers. The controller used is in-house, originally from SanDisk (the two companies are related) and the 3D NAND TLC memory originates from the Kioxia (formerly Toshiba) factories. This BiCS5 memory vertically stacks 112 layers of cells, which is a slightly more advanced technology than what is found on the SN850 (BiCS4 with 96 layers). Guaranteed for five years, the series also offers decent write endurance, between 200 TB and 1200 TB depending on the capacity: 250 GB (for 200 TB of endurance), 500 GB (300 TB), 1 TB (600 TB) and 2 TB (1200 TB).
The mid-range positioning is at the level of theoretical speeds, clearly down compared to the leaders of the genre. In sequential access, the maximum is 5.15 GB/s for 4.9 GB/s in writing. Random accesses are 740 KIOPS and 800 KIOPS in read and write respectively. Enough to place the SN770 right between the SN750 SE and SN850 – the two references also operating in PCIe 4. This also makes this series a competitor to Corsair’s MP600 Core series which offers a fairly similar performance on paper.
Where it gets stuck is probably at the price level. Positioned at €182 in its 1 TB version, the WD Black SN770 will go up against a 1 TB MP600 Core, admittedly a little slower, but sold at €140. Same situation on the 2 TB edition, sold for €435 against €281 for the MP600 Core. The 250 GB and 500 GB versions are available from €72 and €107. Prices that finally position the series against the Corsair MP600 Pro LPX and Seagate FireCuda 530 whose speeds are much higher.
These competing series also come with heatsinks, allowing these SDSs to be used directly in a Sony PS5 console. Purchasers of WD Black SN770 will have to go through the additional purchase of a third-party heatsink to carry out this type of installation; a purchase that further complicates the price positioning.