WD Black 2 full review
The Black 2 is a novel solution to a laptop storage problem. You can have the fast performance of an SSD or the cheap price of a traditional hard disk. Performance on a budget is difficult. ??To blend both decent storage capacity and high performance you might install two drives, SSD and HDD. That's fine in a desktop computer with plenty of spare drive bays, but almost all laptops only have room for a single internal drive. That's where the Black 2 comes in handy. See also Group test: what's the best SSD (solid-state drive)?
The WD Black 2 packages a 120 GB mSATA SSD with a 1 TB hard disk, all in a single laptop-sized 2.5-inch storage device. The two drives share the same bus, so only need one SATA connection for power and data.
This isn't the first time a storage company has combined flash memory with a hard disk. Seagate's Momentous XT solid-state hybrid drives (SSHD) use a small amount of SLC flash memory, just 8 or 16 GB, as a speedy read cache. That drive appears as a single volume in any operating system – Windows, OS X or Linux – with the on-barod controller deciding which blocks are accessed most frequently, then moving them between the flash memory and disk platters.?
The Black 2 comes in a cardboard box which slides open to reveal the drive itself – a 9.5mm-high, 2.5-inch device the same size as a standard notebook drive. You also get a SATA-to-USB 3.0 adaptor, and a USB ‘key' attached to a piece of cardboard.
Rather than containing any software, the USB key actually redirects your web browser to Western Digital's website, in order to download the software that's required for Windows to see both the SSD and hard disk. Without this software only the SSD portion of the Black 2 can be used.
The WD Black 2 works differently though. The drives are completely separate, and appear as two volumes once WD's proprietary software has been installed on your computer.
WD's SmartWare software has to be installed to use the hard disk portion of the Black 2, and this is restricted to Windows PCs and laptops only – there is currently no Mac OS X or Linux compatability. The Black 2's reliance on special software also means the Black 2 can't be used fully on other non-PC platforms, such as a storage upgrade for a console like the Playstation 4.
We installed a fresh copy of Windows 7 onto the Black 2 without any issues. As expected, the Windows installer recognised it initially as just a single 120 GB drive. After that we downloaded and installed the Western Digital installation software. Without even needing the usual Windows reboot, the second partition showed up ready to use, formatted and assigned a drive letter.??In its FAQ, Western Digital goes to lengths to remind users not to span a partition across the SSD and hard disk in the Black 2, including any RAID configuration. If for any reason the SSD fails, the data on the hard disk should be retrievable, as long as the host PC has the Black 2 software installed.
This is one advantage of having two separate volumes: in a combined-drive setup such as Apple's Fusion Drive or RAID 0, if either disk fails you lose all the data on both. If such a thing happens to the Black 2, you may be able to still read from the still-working side. You're also covered by a 5-year warranty.
The TRIM SSD command is also fully supported by the SSD.?
In tests neither the SSD nor the hard disk in the Black 2 broke any performance records. This is expected, since 2.5-inch hard disks are slower than their full-sized counterparts.
For the hard disk component, the empty disk could read and write at the typical speed of a modern 5400 rpm notebook HDD, around 114 MB/s. That was the maximum transfer speed for large sequential files, with small files read and written much slower of course – around 1 MB/s for 4 kB data.
Turning to the SSD side, we found that in line with WD's specfication the write speed is slow – just 149 MB/s in our tests. Maximum sequential speeds were faster and close to what we'd expect of a modern SSD, recording 456 MB/s in CrystalDiskMark with 1000 MB data.
From the same benchmark, we calculated the all-important IOPS figures, which were close to 41,000 write IOPS and 60,000 read IOPS, for 4 kB random data. Those are not especially high figures, and we'd expect closer to 80,000 or even 100,000 for a modern high-performance solid-state drive.
However, much faster access times and greater throughput still delivered superior boot and loading times over a conventional hard disk.
WD Black 2: Specs
- Combined SSD and HDD
- SATA 6 Gb/s interface
- 2.5-inch form factor
- 1.1TB total capacity
- 69.85mm x 100.3mm x 9.5mm
- 5-year warranty