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G-Technology G-Dock Ev review: A new level of external storage flexibility

Looking for a Thunderbolt-only device that your USB 3.0-enabled computers can also take advantage of? The G-Dock Ev from G-Tech is the answer.

Dong Ngo SF Labs Manager, Editor / Reviews
CNET editor Dong Ngo has been involved with technology since 2000, starting with testing gadgets and writing code for CNET Labs' benchmarks. He now manages CNET San Francisco Labs, reviews 3D printers, networking/storage devices, and also writes about other topics from online security to new gadgets and how technology impacts the life of people around the world.
Dong Ngo
7 min read

The G-Dock Ev blends USB 3.0 and Thunderbolt technologies together to offer a fast and flexible storage option. It comes with two TB G-Drive Ev units that can double as standalone USB 3.0 portable drives.


G-Technology G-Dock Ev

The Good

The <b>G-Technology G-Dock Ev</b> and the G-Drive Ev are easy to use, perform impressively, and combine USB 3.0 and Thunderbolt connections to deliver a flexible storage system.

The Bad

With no regular internal-drive support, the G-Dock's storage capacity is capped at only 2TB. The internal drives can be ejected from the chassis far too easily.

The Bottom Line

The G-Dock and G-Drive introduce a new level of flexibility in external storage, and performance is fast.

You can also set up the G-Dock's storage using RAID 1 or RAID 0 and make it work just like any other two-bay Thunderbolt device, such as the G-RAID that came out last year.

The G-Dock Ev offered very good performance in my testing, enough to justify the current price, which fluctuates between $420 to $730 (2TB included). You can also get the 1TB G-Drive Ev by itself for $130. If you're working in an environment where you need to collect or share data between multiple computers and not all of them support Thunderbolt, the G-Dock Ev makes an excellent choice. Those with just Thunderbolt or USB 3.0 should also consider these two, respectively, for their rugged build and fast performance.

Modular design for great flexibility
Announced back in April, the G-Dock Ev is part of G-Technology's Evolution Series of storage devices. This is G-Tech's first approach to the modular design for storage, very similar to Seagate's Universal Storage Module (USM) slot, which works with the Backup Plus portable drive. The G-Dock Ev comes with two G-Drive Ev units included, each being a USB portable storage device by itself.

The G-Dock Ev and two G-Drive Ev units that can also work as USB 3.0 portable drives.
The G-Dock Ev, and two G-Drive Ev units that can also work as USB 3.0 portable drives. Dong Ngo/CNET

Apart from the Micro-USB 3.0 port, the G-Drive Ev also has a SATA port so it can be used with the G-Dock Ev as its internal storage. You can easily insert the G-Drive Ev into the G-Dock Ev via the docking station's front-facing drive bays. This design allows the G-Drive Ev to quickly transform from a standalone portable drive into a full-speed SATA 3 (6Gbps) internal drive. The G-Dock Ev connects to a computer using a Thunderbolt connection, which caps at 10Gbps, double the speed cap of USB 3.0.

In other words, when you get the G-Dock Ev, you get a docking station and two separate storage modules. You can use these modules as standalone USB 3.0 portable drives, or use them inside the G-Dock Ev as Thunderbolt storage. In the latter case, you have two options.

Multiple usage options, but no support for regular internal drives
The first option is to use the two G-Drive Ev modules as two separate volumes. This allows great flexibility because you can pull either of them out at any time to use with other computers as USB portable drives. Each drive bay has a button that protrudes out when the G-Drive Ev is inserted, so you just need to push the button to eject it.

This works best in situations where you need to quickly share or collect data between multiple computers. However, the speed of the storage system is now capped by the speed of the individual drive itself, and there's no data protection in case the G-Drive Ev fails, though you can get more G-Drive Ev units for backups.

The G-Dock Ev is quite compact for a dual-bay Thunderbolt storage device.
The G-Dock Ev is quite compact for a dual-bay Thunderbolt storage device. Dong Ngo/CNET

For real-time data protection or faster performance, you need to use the drives in either RAID 1 or RAID 0, respectively. In this case the G-Dock Ev works just like any other dual-bay Thunderbolt drive. You now can't take out the G-Drive Ev anymore since that will break the RAID setup, especially in RAID 0. In this usage, I find that the G-Dock Ev's drive bay design is a little flawed: the drive bay's eject buttons can be pushed too easily and there's no locking mechanism to prevent accidental drive ejection.

The second minor shortcoming is the fact that the G-Dock Ev doesn't support regular internal drives. And this means its storage, for now, is capped at 2TB. If the device supported standard 2.5-inch hard drives, it could easily increase its storage space to up to 4TB or even more in the near future.

Compact, rugged, and easy to use
Both the G-Dock Ev docking station and the G-Drive Ev module are quite compact. Both have G-Technology's signature aluminum casing with shiny white finish. The devices are very rugged and feel solid in the hand.

The G-Dock Ev has two Thunderbolt ports on the back, which is standard for most desktop Thunderbolt storage devices. The second port is for connecting to another Thunderbolt device in a daisy-chain setup. You can link up to six devices together to one host computer. There's a power button on the back; in my testing, unlike other Thunderbolt devices that share their power status with the host computer, the G-Dock Ev requires you to turn it on or off manually.

The G-Drive Ev has one white status light on the front that flashes white when there's data activity. Out of the box, both drives are formatted in HFS+ and work immediately when plugged into a Mac via the included USB 3.0 cable. You can also use it with a Windows computer once it's reformatted into NTFS.

The G-Drive Ev has both a USB 3.0 port to work as a portable bus-power drive, and a SATA 3.0 port to work as an internal drive of the G-Dock Ev.
The G-Drive Ev has both a USB 3.0 port to work as a portable bus-power drive, and a SATA 3.0 port to work as an internal drive of the G-Dock Ev. Dong Ngo/CNET

When inserted into the G-Dock Ev, the G-Drive Ev also works immediately as a separate volume. If you want to use the two in a RAID configuration, you will need to use Disk Utility, included in Mac OS X, to reconfigure them, which took just a few seconds when I tried it.

The G-Dock Ev's package includes all cables necessary for it to be used right out of the box.

I tested the G-Drive Ev as a standalone USB 3.0 portable drive and the G-Dock Ev hosting two G-Drive Ev units as a dual-bay Thunderbolt storage device. In both cases they offered very fast performance.

As a portable drive the G-Drive Ev topped the chart with 124MBps for writing and 133MBps for reading when used with USB 3.0. When used with USB 2.0, it also scored very high, with 29MBps for writing and 33MBps for reading.

CNET Labs external hard drive USB 3.0 performance (in MBps)
(Longer bars indicate better performance)
G-Technology G-Drive Ev
Toshiba Canvio Slim II
WD My Passport Ultra
IoSafe Solo G3
Canvio Connect
Seagate Backup Plus
Lexar JumpDrive Triton
Toshiba Canvio Desk
LaCie Minimus USB 3.0
LaCie FastKey
G-Drive Slim
WD My Passport Edge
Seagate GoFlex Slim
HP Portable Hard Drive

CNET Labs USB 2.0 external hard drive performance (in MBps)
(Longer bars indicate better performance)
G-Technology G-Drive Ev
Seagate Backup Plus
WD My Passport Ultra
Seagate GoFlex Slim
Toshiba Canvio Slim II
Toshiba Canvio Desk
G-Drive Slim
WD My Passport Edge

I tested the G-Dock Ev both transferring data back and forth with a host computer, which was a MacBook Pro powered by a top-speed solid-state drive (SSD), and when it was used to transfer data to and from another Thunderbolt storage device. The reason for the latter test is because Thunderbolt has a much higher ceiling speed (10Mbps) than an internal drive (6Gbps). I also tested the device making copies of data within itself. And finally I tested it in RAID 1, RAID 0, and a non-RAID setup where the internal drives were used as two separate volumes. The results are shown in the charts below; generally it did well. At most it offered 107MBps when copying within itself, and 224MBps when transferring data to another Thunderbolt device, both in RAID 0. In the same test but in RAID 1, the device registered 59MBps and 133MBps, respectively.

CNET Labs data transfer performance, Thunderbolt only (in MBps)
(Longer bars indicate better performance)
Unit to unit  
Self-read and write  
Promise Pegasus R6 (RAID 5)
G-Technology G-Dock Ev (RAID 0)
Elgato Thunderbolt SSD
G-Technology G-Dock Ev (RAID 1)
Drobo Mini

CNET Labs data transfer performance, Thunderbolt with host (in MBps)
(Longer bars indicate better performance)
Promise Pegasus J4 (RAID 0)
G-Technology G-Dock Ev (RAID 0)
G-Technology G-Dock Ev (JBOD)
G-Technology G-Dock Ev (RAID 1)
Promise Pegasus J4 (JBOD)
Promise Pegasus J4 (RAID 1)
Drobo Mini

In all, the G-Dock Ev and the G-Drive Ev worked very well and I was pleased with their performance.

While the G-Dock Ev's new modular design makes no difference to those wanting to use it like typical dual-bay Thunderbolt storage, it's a great bonus for those who want to also take advantage of USB 3.0 via the included G-Drive Ev modular portable drives. And the fast performance, good looks, and ease of use only make it that much easier to recommend.


G-Technology G-Dock Ev

Score Breakdown

Setup 8Features 8Performance 8Support 8