OWC Mercury Extreme Pro 6G - solid-state drive - review: OWC Mercury Extreme Pro 6G - solid-state drive -

OWC Mercury Extreme Pro 6G - solid-state drive -

Dong Ngo

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.

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6 min read

The Mercury Extreme Pro 6G solid-state drive (SSD) is similar to the OCZ Vertex 3 in more ways than one. It's fast, supports SATA 3 (6Gbps), comes with advanced features, and also takes a long time to be formatted.


OWC Mercury Extreme Pro 6G - solid-state drive -

The Good

The <b>Mercury Extreme Pro 6G</b> solid-state drive supports SATA 6Gbps and offers fast performance. The SSD works in any SATA-based storage application, and its top 480GB capacity version is relatively affordable.

The Bad

The Extreme Pro 6G's performance as a main drive could be better. The drive takes a long time to be formatted, doesn't come with a drive bay converter to work with desktop computers, and its 120GB and 240GB capacities are comparatively expensive.

The Bottom Line

Offering fast SATA 3 performance and compatibility, the Mercury Extreme Pro 6G SSD makes a very good replacement hard drive for any computer, especially one that has built-in support for SATA 6Gbps.

Unlike the Vertex 3, however, the Extreme Pro 6G showed mixed performance in our testing and doesn't come with a drive bay converter to fit well into a desktop computer. At prices of $550 and $295 for the 240GB and 120GB capacities, respectively, the Extreme Pro 6G is also noticeably more expensive than the same capacity models of the Vertex 3. Its 480GB capacity, on the other hand, costs only $1,280, which is significantly less expensive than the same-capacity Vertex 3, which costs around $1,800.

Despite its mixed performance, the Mercury Extreme Pro 6G SSD makes a very fast internal storage device and will definitely improve a computer's performance a great deal when used as the main drive. Even with the expensive prices, it still makes a very good investment. Budget-conscious users, however, should check out the Vertex 3 and the Agility 3 from OCZ for similar performance gains without breaking the bank.

Design and features

Drive type 2.5-inch solid state
Connector options SATA 3Gbps, SATA 6Gbps
Available capacities 120GB, 240GB, 480GB
Product dimensions 9.5mm, 2.5-inch standard
Capacity of test unit 240GB
OSes supported Windows, Mac, Linux

The Mercury Extreme Pro 6G shares the same shape, dimensions, and port design as the OCZ Vertex 3, which is the same design as a standard 9.5mm, 2.5-inch internal hard drive. Unlike the Vertex 3, however, the Mercury Extreme Pro 6G doesn't come with a drive bay converter, meaning it will be a little tricky if you want to use it with a desktop computer. In our experience, however, as an SSD has no moving parts and is very light, you can probably get away with leaving it inside the computer's chassis without screwing it tightly to a drive bay.

According to OWC, the Mercury Extreme Pro 6G offers similar advanced SSD technologies to those found in the Vertex 3. Examples of these include a wear-leveling algorithm and SandForce RAISE. The former ensures that the entire drive's memory cells have the same level of wear, and the latter offers RAID 1-like redundancy for data integrity. Like the Vertex 3, the Extreme Pro 6G also supports RAID configurations.

Similar to the latest SSDs we've reviewed, the Mercury Extreme Pro 6G supports SATA 3 (6Gbps) and is backward-compatible with previous generations of the SATA standard. This means it'll work in any SATA applications. To take advantage of the drive's top speed, however, you'll want to use it with a SATA 3 controller, such as that of a computer powered by Intel's new Sandy Bridge chipset.

We tried the Mercury Extreme Pro 6G in a few different computers, running Mac OS X, Windows, and Linux, and it worked well with all of them, just like any regular SATA hard drive. As with the Vertex 3, the Mercury Extreme Pro 6G took a significantly long time to be formatted in our trials, about 7 minutes to be quick-formatted using Windows 7. Other drives, including the Seagate Barracuda XT, took just a few seconds to be quick-formatted.

Cost per gigabyte
The OWC Mercury Extreme Pro 6G's 240GB version is currently the most expensive among recent SATA 3 (6Gbps) solid-state drives we've reviewed, costing around $2.29 per gigabyte. The second most expensive is now the Vertex 3, which is about 12 cents per gigabyte less. If you want to opt for the top-capacity version, however, the 480GB Mercury Extreme Pro 6G is much less expensive, at just $2.67 per gigabyte; the 480GB Vertex 3 costs $3.76 per gigabyte.

Compared with regular hard drives, however, the Mercury Extreme Pro 6G, like all SSDs, is much more expensive; most hard drives cost just a few cents per gigabyte.

Cost per GB (based on current street price)
OWC Mercury Extreme Pro 6G (480GB)
OWC Mercury Extreme Pro 6G (240GB)

We test SSDs in real-world usage, both as the main drive that hosts the operating system of the test computer, and as a secondary drive, which is used only to store data. Some of our tests gauge the performance of the system as a whole and see how the drive affects its performance. Our data copy tests, however, show the drive's raw data transfer speed when used in real-world scenarios after all overheads.

As the main drive, in a boot time test, the Mercury Extreme Pro 6G helped the system boot up in just 29.4 seconds, which is about the same as the rest of the SATA 3 SSDs we've reviewed. Note that this boot time includes the time the test machine spends going through the hardware initialization, about 15 seconds. In our trials with some laptops, the boot time is much shorter, taking about 10 seconds. In shutting down, the system did similarly well, taking just 5.7 seconds with the Mercury Extreme Pro 6G. To put this in perspective, when we used a very fast hard drive as the main drive, the test system would need about 1 minute to boot up and about 15 seconds to shut down.

In our office performance test, where we time how long the computer takes to finish a comprehensive set of different concurrent tasks--involving Word, Excel, file transferring, and compression--the Mercury Extreme Pro 6G didn't help much, as the test system took 395 seconds to finish the job; the Vertex 3 took 390 seconds. This test, however, is one where the internal storage device plays a very small role in overall performance.

Similarly, in our multimedia multitasking test, which gauges the computer's performance as it converts an HD movie from one format to another while iTunes is converting music files in the background, the Mercury Extreme Pro 6G was the second slowest at 332 seconds. In this test, the Vertex 3 did better with 322 seconds.

The test that shows the drive's throughput speed is the most important of our tests, and here the Mercury Extreme Pro 6G excelled when used as a secondary drive. It scored 262MBps, which is the fastest we've seen.

In this same test, but when the Mercury Extreme Pro 6G was used as the main drive, it was comparatively slow, scoring just 128.77MBps, compared with the Vertex 3's 150.01MBps. Note that in this test, the drive had to perform both reading and writing at the same time. Though not as fast as we expected, the Mercury is still very fast compared with regular hard drives, most of them scoring around 50MBps in the same test. Even when compared with other SSDs, the Mercury is still faster than many.

CNET Labs' system performance scores (in seconds)
(Shorter bars indicate better performance)
WD VelociRaptor 600GB
OCZ Vertex 3
Plextor PX-256M2S
WD VelociRaptor 300GB
OCZ Agility 3
OWC Mercury Extreme Pro 6G

Boot and shutdown time (in seconds)
(Shorter bars indicate better performance)
Boot time  
OCZ Vertex 3
OWC Mercury Extreme Pro 6G
OCZ Agility 3
WD VelociRaptor 600GB
WD VelociRaptor 300GB

CNET Labs' data transfer scores (in MBps)
(Longer bars indicate better performance)
As secondary drive  
As OS drive  
Plextor PX-256M2S
OCZ Vertex 3
OWC Mercury Extreme Pro 6G
OCZ Agility 3
WD VelociRaptor 600GB
Seagate Barracuda XT
WD VelociRaptor 300GB

Service and support
When it comes to storage devices, the length of warranty is the most important factor, and OWC delivers. The company backs the Mercury Extreme Pro 6G with a generous five-year warranty; most SSDs come with three-year warranties.

Add better performance as a host drive and lower the price for the 240GB and 120GB capacities a notch and the Mercury Extreme Pro 6G would make an excellent SSD for your laptop or even desktop computer. In its current state, however, the drive is still a very good investment for those who want to get the most out of their SATA 3-ready computers.


OWC Mercury Extreme Pro 6G - solid-state drive -

Score Breakdown

Design 7Features 6Performance 8Support 8
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