Western Digital caught swapping lower-grade NAND into budget SSD


Posts: 1,184   +20
Staff member
What just happened? Western Digital quietly changed the NAND flash in one of its budget SSDs with a lower-grade version that only performs as well as that of its cheaper brother. While this isn't going to be a deal-breaker for everyone, the company hasn't told reviewers and consumers about it -- a behavior that's slowly turning into a trend.

Buying an SSD can be a daunting task with the variety of options that are available today. Using guides like our own can help you navigate through these waters, but sometimes a manufacturer will decide -- for any number of legitimate reasons -- to quietly change the NAND flash or controller chipset in one or more SSDs that have already been reviewed and received glowing recommendations.

While minor hardware revisions that improve on the initial release for a product are a common occurrence in the tech industry, it's never acceptable when the revised product is inferior in any way to the original and this fact isn't disclosed to reviewers and potential customers. Such is the case of the WD SN550 Blue SSD, a popular budget SSD that has been modified in a way that cripples its write performance.

Model WD SN550 Blue 1TB SanDisk Ultra 1TB WD SN350 Green 1TB
Formatted Capacity 931.3GB 931.1GB 894.1GB
SLC Cache Size 12 GB 10 GB 10 GB
Write Speed w/ Cache 2160 MB/s 1945 MB/s 2030 MB/s
Write Speed w/o Cache 390 MB/s 849 MB/s 376 MB/s

The change was noticed by Chinese news site Expreview, who noticed that Western Digital swapped the NAND on the SN550 Blue SSD for a slightly lower-grade version that doesn't perform nearly as well when you need to copy large files around.

Both the old and the new version achieve write speeds in excess of 2,000 megabytes per second as long as the transfer doesn't exceed the 12-gigabyte SLC cache. However, once that is filled and the SSD starts writing without it, the speed drops from 610 megabytes per second on the old drive to just 390 megabytes per second on the new one.

As noted by Expreview, the performance results of the new SN550 Blue drive are more in line with the cheaper SN350 Green. To be fair, this issue only becomes noticeable if you happen to move large files very often, but even so this doesn't excuse the lack of communication on the part of Western Digital. While not exactly an apples-to-apples comparison, the company did something similar with its HDDs in the recent past and ended up with class-action lawsuits.

This behavior highlights one of the consequences of the ongoing chip shortage -- manufacturers are scrambling to meet a surge in demand for everything that has silicon in it, and in the process they are forced to make sacrifices that are more or less noticeable to the end user. Smaller manufacturers, in particular, may be more prone to this behavior due to their lower negotiation power.

However, after you've seen this with the likes of Kingston, Crucial, Patriot, Adata, and now Western Digital, it certainly isn't a good sign. Consumers don't need to be told about each and every change if the new revision of an SSD performs the same as originally advertised, but they certainly do deserve better than bait and switch.

Permalink to story.



Posts: 356   +969
Yeah, WD is slimy.

Remember when they nerfed the Blue HDD's with SMR instead of CMR?

The CMR version of the WD Blue 6 TB takes 12 hour to rebuild the Raid after a blue screen, the SMR one should take 3 times as much.

No other choice but Samsung SSD's if you don't wanna get conned. I own 3 already.


Posts: 1,049   +855
That would be funny if the people that chose that decision we should remove their vehicles engines be it a Lambo or Benz and shove in a 1980's GM 2.5L and see how they like that.

On a serious note I built a new system with two SSD drives one is Samsung and the other WD. I bench marked both and the WD was just as good if not better than the Samsung one!


Posts: 301   +274
It's called bait and switch, and some others are masters at it (hello, Kingston). Not sure how other customers deal with this, if at all, but I'm punishing them with my wallet. So adios WD, it was great while it lasted (I have a 1 TB SN550 as my data drive, will get something else when I upgrade).


Posts: 1,200   +240
A good friend of mine had her old macbook fitted with two separate SSD: Crucial MX500 and WD Green. she got the WD Green first so it was fitted on the original SATA drive slot, while the MX500 was on the optical drive slot secured with just 3M adhesive.

so one time she accidentally dropped the laptop and guess what? the WD green was totaled. if you look at the teardown videos, both WD Green and MX500 internals are so small they don't even fill half the 2.5" drive. yet, only the WD Green SSD did not survive this ordeal.

strangely I never had any issues with WD HDDs so far, so I guess I should avoid WD SSD so I don't push my luck.


Posts: 424   +220
Like others I have had issues with a few HDDs but this article isn't about reliability, its about sneaky practices.

I moaned about Seagate to someone a while back, as they were and still in my mind the worst. They were all like I got a Seagate 5+ years old still going...

Yeah doofus, when they had a clue. Now they don't.

Having worked in storage the rule of thumb was they are like cars, and built in batches, and if there is a naff one the batch probably was.

Also anything over 2tb has an increased fail rate but that's mech.

I won't trust this article to not buy WD because I would never have Bought a naff WD blue in the first place. Those drives are turd anyway. Who cares what the shove in them.

If they ruin their blacks or reds that's another matter. I'll always research about a drives possible longevity, power, speed etc.



Posts: 32   +45
I always benchmark a new SSD and compare it to what I should be getting according to the reviews. I do this to guard against a weaker/dying unit, which can happen, but I guess this is another good reason.

Avro Arrow

Posts: 2,204   +2,595
TechSpot Elite
It's not really fair to just single-out WD for this when, as others have pointed out, they're not alone with AData and Kingston having done the same thing. It's very possible that companies like Crucial, Intel, Seagate, Team, Corsair and Samsung have done similar things but didn't get caught.

I personally have a WD SN550 that I bought last summer and it was a fantastic deal at the time. It still works beautifully and I use it as my gaming drive. It's especially good at lowering the load times for Civ6 to the point where its speed advantage over a 7200rpm spinning drive is extremely noticeable.

I had initially installed Civ6 to my Barracuda 7200rpm platter drive because I figured that with a turn-based strategy game like Civ6, drive performance wouldn't be as big of an issue as it would for Assassin's Creed: Odyssey that is always loading and flushing textures.

Companies are getting desperate but they have no excuse not to be forthcoming about a product. If it were my company, I would have either discontinued the SN550 (if the better NAND wasn't available for it at all) or I would have added the new product and called it something like the SN525 and offered it for maybe $10 or $15 less. I would NOT have tried to pass it off as the same model.

Changing the RAM to something that hampers performance without changing the model number is a **** move that was perfected by nVidia with the GT 730. I hate things like that.

Uncle Al

Posts: 8,675   +7,584
Tsk, tsk, tsk, tsk ..... and WD was slowly coming back. Looks like it's time for a reset ... and a new CEO to boot ....


Posts: 2,367   +2,511
TechSpot Elite
Hey, they are a tech company, upholding the golden rule of tech.

Do as little work as possible, save money in the worst of ways after all other cost-cutting measures, and then charge as much money as you can to a customer base that will gobble it up like Skittles.


Posts: 7,494   +6,300
Except that the certain crowd that wants to skate through life, doing as little as possible, while having disdain for, and making fun of hard work and success, cant afford Caviar.
Hell, they can barely afford Skittles. šŸ¤£
I was using Caviar as a pun, and I should have said so. Apologies! WD has a "Caviar" line of drives. ;)


Posts: 305   +106
Have any of you who've had WD HDD's fail actually taken the time to figure out why they failed
I've had 20+ WD HDD's in my PC using life and only ever had two die 1 was an 80GB and on was an 1TB but I've had 5 Seagate HDD's and out them only the oldest 545MB HDD is still running

as for what the did to the Sn550 NVMe SSD well that' akin to putting lambo badges on a toyota corolla and calling it the same thing


Posts: 36   +27
Yeah, WD is slimy.

Remember when they nerfed the Blue HDD's with SMR instead of CMR?

The CMR version of the WD Blue 6 TB takes 12 hour to rebuild the Raid after a blue screen, the SMR one should take 3 times as much.

No other choice but Samsung SSD's if you don't wanna get conned. I own 3 already.
Tough luck. Samsung just did the same: https://www.techpowerup.com/286008/...changes-components-for-their-970-evo-plus-ssd

I guess this about covers all major manufacturers who have done this. Also in Samsungs case the result is similar. Once you exhaust the SLC cache the speed drops to a lower level on the new revision compared to the old one.