SanDisk Extreme II SSD review

Prices of SSDs have dropped considerably in the past two years, and with affordable flash drives like this year-old favourite, the SanDisk Extreme II, we can all now ‘go flash’ for the magic figure of 50 pence per gigabyte. It takes a 7mm high form, and is constructed around a cast aluminium shell with a total weight of 57g. Also see: What’s the best SSD

The Extreme II uses SanDisk’s own NAND flash stock, based on 19nm MLC. In charge of this is the Marvell 88SS9187 controller, which we’ve also seen used to good effect in last year’s Crucial M500 and Plextor M5 Pro – both premium products and award-winning drives. One difference may lie with the firmware loaded, which is believed here to be SanDisk’s own. Data is buffered by a healthy 256MB of fast DDR3 cache. Firmware upgrades are available through SanDisk to patch defects, although we could only find a Windows utility to do so.

Like any self-respecting SATA Revision 3 solid-state drive, simple sequential tests were nudging the interface limit – with sequential reads at least. The ATTO Disk Benchmark tool here showed reads up to 557MB/s and writes not too distantly behind at 519MB/s.

Probing further with CrystalDiskMark indicated superb small file transfer characteristics. But first the headline sequential speeds: 514MB/s reads and 483MB/s writes. We checked with both default random data and also with the 0x00 string-o’-zeroes test, and found exactly the same performance within measurement error, demonstrating why Plextor can truthfully market its SSDs – which use the same controller – as TrueSpeed. In other words, performance won’t vary depending on what type of data you’re writing.

Down at the small random file level, the SanDisk Extreme II was essentially at the milestone 100k IOPS level. CrystalDiskMark reported 99,328 IOPS for random 4kB reads at 32 queue depth. Writes here were 78,848 IOPS. For single-threaded transfers, we saw 4k random reads and writes at 35- and 97MB/s respectively, suggesting a bias toward write speed. In AS SSD, the Extreme II gained an overall score of 1062, with faster file reading when stacked to 64 threads – 349MB/s reads versus 280MB/s writes – and great 4k writes of 79MB/s against 28MB/s reads. The SanDisk Extreme II would have stood out as a well-balanced high-performance SSD among its peers 12 months ago. It still does and now additionally benefits from keen pricing.