WD Red SA500 NAS SSD Review: Excellent for PCs, Too!

The WD Red SA500 SSD is Western Digital's formidable contender to Seagate's IronWolf 110. The new NAS-centric solid-state drive proved to be faster than its rival in my testing.

Most importantly, it costs significantly less, just around 15 cents per gigabyte, than some 25 cents of the Seagate. And it's also more versatile, available in both 2.5-inch and M.2 form factors.

The new WD Red SSD isn't perfect, though, since it has a significantly lower endurance rating than the Seagate counterpart. But that's just a minor shortcoming.

If you're looking for a reliable SSD to use inside your NAS or as a replacement drive for your computer, the WD Red SA500 is an excellent buy.

WD Red SA500: A versatile standard SSD

As mentioned above, the WD Red SA500 comes in two flavors. It's available in up to 4TB in the standard 7mm 2.5-inch (laptop) form factor and up to 2TB in the newer M.2 2280 design.

If you're not sure which is which, I talked about them in detail in this post. It's important to note that the M.2 version doesn't support the NVMe interface. It remains a SATA drive.

The 2.5-inch design is a perfect fit for mini NAS servers, like the Synology DS620slim or the DS419slim, and the M.2 can work right away as a cache for the DS1019+ though, in this case, I wish it were an NVMe drive.

Of course, you can use an adapter (not included) to use the SA500 in any server of any physical size. And both drives will also work with any standard computer that supports their interfaces.

The SA500 uses SATA 3, which caps at 6Gbps. Considering most NAS servers' performance is limited by their network connection, which generally caps at 1Gbps, the SA500 is more than fast enough.

Comparatively low endurance

Endurance is the amount of data you can write to an SSD before you can't anymore. The higher the rating is, the more writes you can perform on a drive. We measure endurance by the number of terabytes that can be written (TBW). A higher-capacity drive of the same model generally has higher TBW.

The Seagate's IronWolf 110 has the highest endurance I've seen in a standard SSD. Its 480GB capacity, for example, can handle 875 TBW. For comparison, the 500GB WD Red SA500 can take only 350 TBW, less than half.

While that sounds like a big gap because it is. Endurance is necessary since NAS servers are designed to work 24/7 with lots and lots of transactions.

But keep in mind that 350TB is already a massive amount of data. If you write 50GB—about two Blueray movies worth of data—to a 500GB WD Red per day and every day, it'll still take you some 20 years to wear it out. The 1TB and 2TB versions will take you 40 and 80 years, respectively.

In fact, the SA500's endurance easily beats that of most conventional SSDS. The 480GB Crucial BX500 that came out earlier this year, for example, has an endurance rating of just 120 TBW. Even the more venerable Samsung 860 Evo's 500GB version has a lower endurance rating of 300 TBW.

So, higher endurance is always better. But, at some point, it doesn't matter much anymore because you will likely need to replace or decommission the drive for other reasons before it runs out of writes. What's important is the warranty that the WD Red SA500 shares with the Seagate IronWolf 110—both have a five-year warranty.

WD Red SA500: Hardware specifications

Being NAS-specific only means that the SA500 has a higher endurance and is better equipped to deal with 24/7 applications than traditional SSDs. In return, the drive might not have features turned for standard usage, such as lower power usage or built-in hardware encryption.

On this matter, WD told me that while the SA500 is "geared for the additional writes/reads" in 24/7 NAS operations, it will work fine for any standard PC setup.

	500GB	1TB	2TB	4TB
Form Factors	2.5-inch 7mm / M.2 2280	2.5-inch 7mm / M.2 2280	2.5-inch 7mm / M.2 2280	2.5-inch 7mm
Product Number	WDS500G1R0A / WDS500G1R0B	WDS100T1R0A  / WDS100T1R0B	WDS200T1R0A / WDS200T1R0B	WDS400T1R0A
NAND Flash Type	WD 3D NAND	WD 3D NAND	WD 3D NAND	WD 3D NAND
Interface	SATA 6Gbps	SATA 6Gbps	SATA 6Gbps	SATA 6Gbps
Sequential Read	560 MB/s	560 MB/s	560 MB/s	560 MB/s
Sequential Write	530 MB/s	530 MB/s	530 MB/s	530 MB/s
Random Read	95,000 IOPS	95,000 IOPS	95,000 IOPS	95,000 IOPS
Random Write	85,000 IOPS	85,000 IOPS	85,000 IOPS	82,000 IOPS
Endurance (Total Bytes Written)	350 TBW	600 TBW	1300 TBW	2500 TBW
Mean Time Between Failures (MTBF, hours)	2,000,000	2,000,000	2,000,000	2,000,000
Power Consumption (Active)	52mW	60mW	60mW	60mW
Weight	7g (M.2) / 37.4g (2.5-inch)	7g (M.2) / 37.4g (2.5-inch)	7g (M2.) / 59.4g (2.5-ich)	59.4g
MSRP	$82.99 / $79.99	$142.99 / $139.99	$282.99 / $279.99	$579.99
Warranty	5 Years	5 Years	5 Years	5 Years

WD Red SA500: Impressive performance

Western Digital provided me with four 2TB SA500 drives—two of each form factor—for testing, and they all did very well.

Great for standard PCs

I first tested them as a replacement drive for a conventional computer. The 2.5-inch drive fitted any applications in which I used a regular SATA hard drive, and the M.2, which has both E- and B- keys, worked well with my test desktop.

It will work with almost all desktop computers via a PCIe adapter card, by the way.

As for performance, the SA500 was impressive. The sequential (copy) test averaged almost 500 MB/s and more than 525 MB/s for writing and reading, respectively.

When I made it do both reading and writing simultaneously, the drive still registered 250 MB/s. What's most noteworthy is that it beat the Seagate IronWolf in all of these tests, albeit only by a small margin.

I tested the WD Red SA500 with lots of data (almost 600 GB) at a time to see if performance would be consistent throughout, and it was.

Excellent for NAS servers

In the random access tests, the WD Red SA500 topped the chart in writing. In writing, it was right in the middle but still significantly faster than the Seagate IronWolf 110. Fast random access speeds will translate into fast database access, application launching, and speedy executions of online transactional processing (OLTP) tasks.

In other words, the WD Red SA500 will work well for its intended role as a NAS SSD. And it did in my real-world anecdotal tests.

Like the case of the Seagate drive, I tried the WD Red SA500 with a couple of Synology NAS servers, including the DS620slim and the DS410slim.

It's important to note these servers (as well as most existing home and business NAS boxes) hook to a network via a Gigabit connection. As a result, 1Gbps is their top data throughput speed.

Since hard drives are already much faster than that, upgrading these servers' storage to SSD won't improve their connection speed much, if at all. If you want to see higher connection speeds, you'll need to get a server with a multi-gig network port and use it with a multi-gig router or switch.

But all servers will benefit from the WD Red SA500 drive, just in different ways.

For example, for testing, I used two drives in a RAID 1 volume on the DS620slim. I then used that volume to host a Windows Server 2016 virtual machine. Via a remote desktop connection, the VM felt just like it was a real machine.

On top of that, the NAS server itself also booted a lot faster, and its applications now launched instantly.

Comparatively, the Seagate IronWolf 110 SSD delivered about the same experience but at a much higher cost. By the way, the WD Red NAS drive was cooler to the hand than the Seagate counterpart in extended operations. 

Conclusion

The new NAS-centric WD Red SA500 is an excellent SSD option that's fast, spacious, and affordable.

If you have rare NAS applications that require extreme endurance, the Seagate IronWolf 110 might be a better fit. Otherwise, a couple of WD Red SA500 drives will give you a killer NAS setup at a much friendlier cost.

Don't have a server? The WD Red SA500 is also an excellent SSD upgrade for any desktop computer. Get one, and you won't be disappointed.