PLEASE NOTE: We had a major data loss on 01/07/2013, however, we were able to recover all but four reviews and one news article. This review was one of the lost four. Due to this, we had to re-run benchmarks are re-write the reviews, so, there will be some discrepancies between this new version and the lost version.


COMPARISONS: We will be running our SSD COMPARISON ARTICLE after all SSDs have been reviewed individually. This comparison will compare all our SSD samples, so, this article will not contain any comparisons with other drives. We hope you return to read our full SSD comparison, to see which drive comes out on top!

ADATA isn’t one of the most well known SSD manufacturers, however, their premium products, excellent performance and constantly growing product lineup are as impressive as any company. Today we review their XPG (Xtreme Performance Gear) SX900 high performance SSD – lets see how it fared!

The XPG SX900 comes in a burshed metal casing; a very stylish and premium look. ADATA use third party components in this product, adopting a Sandforce 2281 controller with a modified firmware. Sandforce generally reserves some of the drive’s capacity to increase durability (this is why you see 120GB, 240GB and 480GB drives), however, ADATA have removed this reservation of space to make the full 256GB usable, presumably without affecting durability.
While many modern drives are equipped with this modification ADATA were one of the first, if not the first to do so.

The drive has gone through a number of revisions since it was originally released, now using sixteen chips of 19nm Sandisk NAND (on the 256GB version). The SX900 comes in a convenient 7mm form factor, allowing use with most ultrabooks. The company are also kind enough to throw in a 3.5″ bracket (with screws) to assist in the mounting of the drive. Also included is a key for a full copy of Acronis True Image HD, a software which assists in backup/restore and disk migration. This software sells quite expensive, so, it is a nice bonus from ADATA!

On the box, ADATA claim the drive can perform at up to 550MB/s sequential read and 530MB/s sequential write (again, for the 256GB version – other capacities will vary) with a maximum of 91,000 random write IOPS. This drive, as with most, supports RAID and TRIM and comes with a three year warranty, which may be a bit short for heavy users. The drive weighs only 68g, so, it feels very light in your hand. Size measures up at 100mm x 69.85mm x 7mm.

Currently on Amazon, the drive is available at a price of £180.99 in the UK and $189.99 in the US, so, quite the UK price is a lot higher (prices as of time of writing), however, it can be found cheaper with less well-known online sellers. This pricing puts the drive at £0.70 per GB and $0.74 per GB, so, the drive prices at the average rate in the UK and the US.

Now it’s time for some benchmarks. Again, please note, all comparisons with other drives will be carried out at the end of the feature in our SSD comparison article.

ATTO Disk Benchmarking Tool
ATTO is one of the most trusted and reliable disk benchmarking utilities available. The figures given by ATTO are the most accurate way of identifying the drives maximum capability if it were pushed beyond real-use limits and brought to theoretical maximum performance. As you can see, the drive came extremely close to its advertised read speed, but a fell a bit lower on the write speed – still staying at impressive rates.

8192KB Read – 547.10MB/s
8192KB Write – 512.17MB/s

32KB Read – 401.76MB/s
32KB Write – 423.19MB/s

CrystalDiskMark is one of my personal favourites in regards to drive benchmarking, as it often gives a very accurate figure as to how your drive will perform if it is pushed to its limit, whereas you usually will not be able to reach the figures provided in ATTO manually. CrystalDiskMark tests sequential speed, as well as a number of random read/write tests for 512K and 4K. As you can see, the SX900 dips in sequential, but performs very well in the random read tests.

Sequential Read – 509.2MB/s
Sequential Write – 494.9MB/s

512K Read – 428.7MB/s
512K Write – 432.6MB/s

4K Read – 41.7MB/s
4K Write – 81.3MB/s

4K QD32 Read – 323.1MB/s
4K QD32 Write – 359.7MB/s

SiSoftware Sandra
SiSoftware Sandra is another tool used by many benchmarkers to see if the drive is consistent across multiple tests in different benchmarking tools. The drive does very well in sequential read, but Sandra isn’t a huge fan of its write performance, unlike some of the other tests…

Sequential Read – 539.2MB/s
Sequential Write – 373.2MB/s

The SX900 comes very close to both its rated speeds (read and write) in both ATTO and CrystalDiskMark, showing some very impressive random read/write performance in the latter. However, SiSoftware Sandra doesn’t rank its write speed very well, which may show a little weakness in some area of the SSD. Overall however, the performance offered is very high and the price is reasonable. The drive, in my opinion, deserves a gold award. There are cheaper alternatives that come close to this level of performance, but the random read and write speeds are very impressive.