WD Red SA500 M.2 1TB NAS SSD review - Introduction

Western Digital RED SA500 M.2.1TB NAS SSD
A SATA3 M2 Storage unit designed for NAS

Color me red, but populating NAS servers with an SSD is the next big trend for that storage solution. With NAND layers going up, prices coming down and storage volume size growing we just had to check out the 1 TB SA500 from Western Digital. The product while being an M2 unit, is SATA interface bound, so will this unit be fast enough for a 10 Gbit/s NAS server? With a rather properly volume size of 1024 GB, we check out the SA500 from Western Digital, while we reviewed the NVMe M2 SATA3 unit, it is also available as regular SATA3 unit (2.5" SSD). WD has been releasing this mostly for SSD caching solutions in a NAS, a popular feature on NAS servers that speeds up the data you read or write a lot by passing them through NAND storage for faster access times. But on the SATA interface these products are rated speed of 500 MB/sec, much like a regular SATA3 SSD.  WD Red NAS SATA3 SSDshowever been designed and tested for 24/7 operation and that is a different point of view compared to say a PC or Laptop. WD mentions it delivers increased endurance and with 2.5” and M.2 form factors and capacities from 500GB up to 4TB* (2.5” only), the WD Red SA500 NAS SATA SSDs might be an attractive alternative. 

• Storage optimized for caching in NAS systems to rapidly access your most frequently used files.
• Superior endurance can handle the heavy read and write loads demanded by NAS, giving you the reliability you need in a 24/7 environment.
• Purpose-built for NAS with proven Western Digital 3D NAND to deliver maximum SATA performance to both home and business users.
• Reduces latency and improves responsiveness for OLTP databases, multi-user environments, photo rendering, 4K and 8K video editing, and more.
• Available in 2.5" and M.2 form factors to fit the slots in modern NAS systems.
• Capacities from 500GB up to 4TB (2.5" only) gives you the flexibility to customize your NAS to meet your most demanding storage needs.
• Form Factor m.2 2280
• Interface SATA III
• Dimensions (L X W X H) 3.15" x 0.87" x 0.09"
• Sequential Read Performance 560MB/s
• Sequential Write Performance 530MB/s

We had the opportunity to test the 1TB model in an M2 form factor. This NAND storage unit once again SSD has SanDisk written all over it, literally. The Western Digital WD RED SA500 is an M.2 2280 SSD with a storage capacity of 500 GB, 1TB and 2TB. The regular SATA3 version even is offered at 4 TB. 

WD having acquired Sandisk, that NAND is fabbed by them we expected the controller to be from them as well, however as it turns out that is a Marvell's 88SS1074 controller, paired 3D TLC NAND memory. WD Red SA500 offers up to 560 MB/s sequential read speeds, up to 530 MB/s sequential write speeds, and up to 95K/85K random read/write IOPS. That might not seem like a lot and yeah it isn't, but remember .. NAS even a unit with 10 Gbit/s LAN jack unit would not pass 600 MB/sec so it is balanced more or less in that category. The SA500 SSD allows you to purchase this storage in the 15 cents per GB region. Currently, that's 150 USD for the 1TB model (price at the WD store at the time of writing this article). The performance will differ slightly with different volume sizes as smaller versions use less NAND channels and thus have slower writing. Let me quickly and clearly reiterate that the SSD might run over PCIe, it, however, follows the SATA protocol and not NVme. This last fact immediately poses an issue as many modern NAS servers support NVMe only, not SATA3 over M2. Realistically you are better off with the 2.5" SSD version of the SA500 series to be safe (however at the cost of one drive bay in your NAS).