ADATA XPG SX900 256GB SATA 3 SSD Review – Expanded Capacity and SandForce Driven Speed

Back In February, we published an article with respect to LSI SandForce releasing code that would enable the production of ‘SandForce Driven’ SSDs with increased capacity, a whopping 7% additional capacity in fact.

In other words, the consumer would see LSI SandForce performance in 64, 128, 256 and 512GB drives vice the standard SF capacities of 60, 120, 240 and 480GB.  This was great news but the question of performance was definitely present in countless SSD forum threads.

In an attempt to answer a question brought forward in a comment at Anandtech, (as they were kind enough to quote our release) a very colorful conversation ensued with respect to where this space would be found and any performance implications that might result.  In the end, we are happy to revisit this topic and our report today is on the ADATA XPG SX900 256GB 6Gbps SSD, this SSD being the first release of a new generation ‘SandForce Driven’ SSD actually marketed in a 256GB capacity.  Grab a seat because you are going to be a bit surprised at the performance we think.


The ADATA XPG (Xtreme Performance Gear) SX900 SSD is available in capacities of 64, 128, 256 and 512GB and is a SATA 3 SSD with listed performance as high as 550MB/s read and 530MB/s write transfer speeds.  Although there is no mention of IOPS, a feature noted on the site is ‘Max 4k Write IOPS’ so we would hazard to guess that this SSD will hit somewhere in the area of 80,000 IOPS at low 4k aligned random write disk access.

blankThe exterior packaging contains the XPG (Xtreme Performance Gear) SX900 SSD, a 2.5″ to 3.5″ desktop adapter, screws, a Quick Start Guide in several languages as well as a free download of Acronis True Image HD for system migration.


The casing of the SX900 is of black metal and its base plate is secured by four screws, one of which is covered by security tape and any damage to this tape would void the three year warranty.

blankblankThe printed circuit board (PCB) contains the SF-2281 processor and 16 pieces of Intel mlc synchronous NAND flash memory (29F16B08CCME3), each module being 16GB in capacity for a total capacity of 256GB.

blankIn a normal ‘SandForce Driven’ SSD, this is the point where we would explain that one module remains proprietary to the needs of over provisioning and firmware, but not with the SX900.  This is a full fledged 256GB (238GB formatted) SandForce Driven 6Gbps SSD and it is the first of it’s kind on any reviewers bench.



  1. blank

    I don’t think it’s entirely unexpected that ditching RAISE would help increase speeds somewhat. After all, the drive isn’t having to write the necessary parity(?) data anymore to recover from a die failure. With that said, I’ve seen increased write performance from SF’s using the new reference 5.02a FW anyway.

    So it looks like you do get slightly better performance overall and more capacity in exchange for less failure tolerance.

  2. blank

    It would be interesting to run a pair of these in RAID 0 to see what the low RAISE does to performance.

  3. blank

    Can’t see how there would be any major surprises, Crucial have been using the 0% over-provisioning for years, The only over-provisioning they’ve had has been the difference between the size of actual memory modules ( gigabytes ) and the actual size of the ssd drive ( Gibibytes ) it still leaves 7% difference for over-provisioning, which is classed as 0%.

    More over-provisioning still makes for a better ssd drive where it matters, but I guess size is everything as far as the market is concerned.


  4. blank

    This is a great review you have there as usual 🙂

    I am Muhammad Al-Jawhary, an Arab reviewer and technical editor, and I have a 128GB sample of the drive that I have reviewed here:

    That makes us two sides of the same coin, you have done the only review in English (as far as I know), and I have done the first and only review in Arabic, too 😀

    The performance is great, and it has 8 GB more than its brother; the S511.

    • blank

      Ummm isnt that my photo of ‘all the ssds’ in your review? I would appreciate the link back to our site and article if you are using any of our literature or piks.

      • blank

        Thanks for your reply, it is a great pleasure to be here 🙂

        Actually, it is your pic, and the pic has a hyperlink embedded (If you press the image, you will be directed to the great article).

        We may have some future cooperation together, I may be able to translate some of your guides and articles and post them in the Arab world, and of course, the credit is all yours, not mine.

      • blank

        When I click on the pik, it brings me only to the pik…. Can we fix the link so it goes to the article? And yes, I am sure we can affiliate post for one another in the future.

      • blank

        Actually, the image has a hyperlink as I said before, but the site uses a script to show the images, which in turn hides the hyperlink. Nonetheless, I have added a credit line under the photo that contains the link. Sorry for the inconvenience 🙂

        Have you seen those numbers I got with the drive? They used asynchronous NAND flashes with the 128GB version! The same NANDs used with Kingston’s SSDNow V+200.

  5. blank

    There is a slight inaccuracy in your reviews which is (implicitly) already mentioned above, but which i’d like to clear up. Flash memory has raw capacities of binary powers, this one e. g. has a raw capacity of 256 * 2^30 = 274877906944 bytes = 256 “GiBi” Bytes. Vendors prefer to use decimal powers, as the numbers are slightly higher, so this SSD has a raw capacity of 275 * 10^9 Bytes = 275 GB. 7% of these are used for over-provisioning leaving the user with 256 GB = 238 GiB. Windows, again, uses binary powers to display drive capacities, so the latter number is what you see there. (No, NTFS formatting doesn’t swallow 18 GB of the drive capacity. 😉 Other Sandforce SSDs with 240 GB = 223 GiB user capacity use 14% of the raw flash capacity for over-provisioning.

Leave a Reply

Your email address will not be published. Required fields are marked *