In assimilating SanDisk, Western Digital has reused its HDD branding on client SSDs: WD Inexperienced, Blue and Black can both check with mechanical exhausting drives or SSDs. The WD Blue model is used for many mainstream merchandise, which suggests SSDs SATA drives. The primary WD Blue SSD launched in 2016 used planar TLC NAND and Marvell management with the same old quantity of DRAM for a mainstream SSD. The following yr, the WD Blue was up to date with 3D TLC NAND, permitting it to compete with the Essential MX Sequence and the Samsung 850 EVO. There have been no adjustments to the WD Blue in 2018, however costs had been lowered to maintain up with the remainder of the business: The $ 1 TB, which debuted at $ 310, is now being offered for $ 120.
SanDisk's 64-layer 3D TLC NAND is nearing the top of its product cycle, however they and different NAND flash makers are in no hurry to change to 96L NAND WD Blue. As a substitute, Western Digital selected emigrate the WD Blue model into one other market phase. After the WD Black has established itself as a high-end NVMe product, there’s room for an entry-level NVMe SSD and the brand new WD Blue SN500. That is little greater than a rebranding of an current OEM product (WD SN520), simply as the present WD Black SN750 SSD is predicated on the WD SN720. The SN520 was introduced greater than a yr in the past however as an OEM product we couldn’t get a tester. As with the high-end SN720 and SN750, the SN520 and WD Blue SN500 use Western Digital's NVMe inside SSD controller structure, however in a cut-down implementation with solely two PCIe lanes and no DRAM interface. The high-end model of this controller structure has confirmed to be very aggressive (particularly for a first-generation product), however to date solely the SN500 datasheet is obtainable to evaluate the low-end controller.
WD Blue SN500 specs
M.2 2280 One-sided
NVMe PCIe three x2
Western Digital in-house
SanDisk 64-layer 3D TLC
None (host reminiscence buffer just isn’t supported)
1700 MB / s
1700 MB / s
1300 MB / s
1450 MB / s
four KB Occasional studying
4KB random writing
(22 ¢ / GB)
(16 ¢ / GB)
Excessive-end shopper / client NVMe SSDs use all PCIe three.zero x4 interfaces, however NVMe's entry-level market is cut up between four- and two-track controllers. Two-track controllers are typically cheaper and, on account of their smaller measurement, enticing for small type issue units that aren’t appropriate for a full 22×80 mm M.2 card. The WD SN520 is a 22x30mm design that can also be accessible in card lengths of 42mm and 80mm. Nonetheless, the commercially accessible WD Blue SN500 is simply offered within the 80mm size, which is the most typical for M.2 drives for finish customers.
Switching from SATA to NVMe means the brand new WD Blue SN500 will ship a lot greater peak efficiency. Nonetheless, utilizing a DRAM-free controller could cause instances the place excessive workloads carry little enchancment and even efficiency degradation. The SN500 controller doesn’t use the NVMe Host Reminiscence Buffer however accommodates an unused quantity of reminiscence on the board for the same objective. Because of this omitting the exterior DRAM from the exhausting disk just isn’t as dangerous as with DRAMless SATA exhausting disks just like the WD Inexperienced SSD.
Though the brand new WD Blue SN500 affords much better efficiency than the present WD Blue SATA SSD, it can nonetheless take an enormous step backward by way of capability: the SATA product line ranges from 250 GB to 2 TB, however the SN500 is simply supplied in capacities of 250 GB and 500 GB. We hope Western Digital will be capable to improve WD Inexperienced on the vegetation to maintain inexpensive 1TB drives in its portfolio.
The MSRP for the WD Blue SN500 is a number of above the present retail promoting worth for the favored SATA SSDs that they intend to succeed. Western Digital didn’t point out when the SN500 will hit the market, however after immediately's announcement, there’s prone to be no main delay as this has been transport to OEMs for a yr.