Western Digital – just WD to its friends these days – spotted a rich untapped vein when it launched the WD Red hard disk last year. The 3.5in SATA Red disk neatly filled the gap that existed between the slow-spin Caviar Green drive, oft installed in consumer network-storage boxes, and the RE-4 business and enterprise hard disk, optimised for filling racks upon racks of network-storage shelves. See all Storage device reviews.
But the WD Red was no real enterprise drive itself, built down to a price which meant it lost out on pro features such as StableTrac, with the platter’s motor shaft secured at both ends. Take a look at: what's the best NAS device?
Tricks like this help drop frame vibration – without it, WD only rated the WD Red good for use in NAS enclosures up to five bays big. Beyond this, it told us, the combined vibration of all disks at work could be enough to cause seek problems with the read/write heads hunting across the disk platter, and disks getting knocked out of the RAID.
Filling the space between the Red and the Re, as the RE-4 is now known, is the new Se hard-disk drive. Instead of the mysterious IntelliPower slow-revving spindle speed of the Green and Red economy drives, the WD Se is a full-blooded 7200 rpm disk, certified for 24x7x365 operation in enterprise datacentres.
This hard disk does include StableTrac to stabilise the platters, as well as WD’s rotary accelerated feed forward (RAFF) technology, a system used in its Velociraptor drives to monitor and control vibration in real time through sensor feedback.
WD’s assurance of longevity is reduced with the Se, compared to the Re – just 800,000 hours mean time before failure (MTBF) against the latter’s 1,200,000-hour figure. And load/unload operations are rated half that of the Re too, at 300,000 cycles.
Note that the Se actually has a shorter lifespan and load-cycle rating than the cheap WD Red, with its 1,000,000-hour MTBF and 600,000-cycle listed specifications.
You should find the WD Se available in three large sizes – 2, 3 and 4 TB. We tested the 4 TB disk for its performance.
WD Se 4TB: Performance
As a full-speed hard disk, you can expect full-ahead performance. And while spinning disk is left for dust by the solid-state alternatives this WD Se showed great performance from the traditional technology.
In simple sequential reads the disk hit its peak performance of 189 MB/s in the ATTO benchmark with 8 MB data. Write speed in the same test was conspicuously lower, but not significantly so at 176 MB/s.
The HD Tune Pro test showed a top read speed of 166 MB/s, dropping to minimum of 87 MB/s at the disk centre. This gave an average read speed of 135 MB/s. Write speed was effectively the same in this benchmark. HD Tach also reported the same performance for read and write in its longer test, agreeing at 160 MB/s.
CrystalDiskMark also let the WD Se show a clean pair of heels, with 176 and 168 MB/s respectively for sequential reads and writes, dropping to 59 and 103 MB/s for 512 kB data samples. Down at the smallest level, 4 kB read and write results were low as we would expect, here just 0.8 and 1.6 MB/s.
Used in a large RAID array, we can attest to the drives’ quiet and relatively low-vibration qualities. Set up in a Synology DS1813+ they exhibited unusually peaceful operation for a large RAID 5 setup.
WD Se 4TB: TCO and longevity
The 4TB WD Se is currently priced almost exactly halfway between the Red and Re models, around £210 against £160 and £300. It has initial performance the same as the more expensive enterprise disk: the difference may lie in longevity, with the Se rated with three-quarters the lifespan. But three-quarters the price of the Re would put the Se at around £225, so this new disk would seem to offer sound economic sense, providing you do include the labour and potential downtime of replacing disks in several years time.