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Looking for new SSD that correctly reports DRAT or RZAT support


Junior Member
Aug 6, 2004

From the recent recently released sata SSDs, a good few new models - despite being RZAT technically - don't report it at all. Neither basic deterministic read after trim, not deterministic read zero after trim.

A few recent models that report basic trim support and nothing else (with most recent firmwares as of this writing):

- crucial mx500 (mx300, even ancient m4 - reported rzat)
- samsung 850s & 860s (both pro and evo) (840pro reported rzat)
- adata sx950u (800u reported rzat, not sure about 900u)

Particularly surprising are samsung "pro"s in the above list.

While this would be of no issue normally (as they all behave in rzat fashion as far as I know), some controllers like LSI 2308 have "sensitive" firmware and block trims altogether if they don't detect at least DRAT feature.

So my question is if you can suggest some other brands/models - that do report rzat or at least drat - similar in price/market position to the models listed above.

The support can be easily checked with hdparm tool (e.g. hdparm -I /dev/sda), if the disk supports it it will return (among other features):

- for drat: "Deterministic read data after TRIM"
- for rzat: "Deterministic read ZEROs after TRIM"

Billy Tallis

Senior member
Aug 4, 2015
I suspect that reporting those features may now be regarded as an "enterprise" feature to be used for product segmentation. This and SLC caching are the primary differences between the 860 EVO and the 860 DCT.

Unfortunately my benchmark scripts aren't currently logging this info, just basic SMART indicators and some NVMe information, so I'm not able to consult my database to check on this. But I'll add hdparm logging so that this info will start to accumulate as I continue testing.
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Reactions: cbn


Junior Member
Aug 6, 2004
Thanks for info. And yea, I have the same fears that they will maybe try to segment the market with something even as basic as that.

On a related note, new MX500 firmware "should" be out soon, so there is small hope they will change that (mentioned it on their forums as well).

Checking for those bits in future ssd-related storage tests will be great, thanks.