Apple and Intel announced the Thunderbolt variant of Intel's LightPeak interconnect technology this past February with emphasis on high throughput speed of particular benefit to storage devices. Promise Technology's Pegasus R6, the first Thunderbolt-enabled storage device on the market, for the most part delivers.
Effectively this is a Mac-only storage peripheral, as Apple's newer desktops and laptops are currently the only computers on the market with the necessary Thunderbolt port. The Pegasus R6 doesn't support other data standards like USB and FireWire out of the box, and given the prices of $1,500 for the 6TB version and $1,999 for the 12TB version, the R6 is a hefty investment. We expect that the price will come down as more Thunderbolt storage devices come to market, but if you need fast, high-capacity storage today, the Pegasus R6 is the fastest external RAID array currently available.
|Drive type||External Thunderbolt hard drive|
|Available capacities||6TB, 12TB|
|Product dimensions (LWH)||7.3x7.7x9.9 inches|
|Capacity of test unit||12TB|
|OSes supported||Mac OS X 10.6.8 or later|
|Software included||Pegasus utility|
Design and features
The Pegasus is about the size you'd expect a storage device that hosts six 3.5-inch internal hard drives to be: it's very large. Nonetheless, like all devices made to work with Macs, the device manages to remain visually appealing, with an all-aluminum chassis. On the back, the R6 has a standard power connection port similar to that of a desktop computer, a big ventilation fan for the hard drives, another smaller vent for the built-in power supply, and two Thunderbolt ports. You can use one of these ports to connect the drive to the host computer using a Thunderbolt cable, which unfortunately is not included and costs another $49. With the other port, you can daisy-chain up to five other Thunderbolt devices, or a Mini DisplayPort monitor, without reducing the connection bandwidth, per the Thunderbolt standard. We connected two Pegasus R6 units together in our testing and they indeed suffered no drop-off in performance.
On the front of the R6, in addition to standard power button and status lights, you'll find the six drive bays. You can pull the drives out easily via small latches that are sturdy enough to prevent you from pulling a drive out accidentally. Once you remove a drive tray, you can install or replace a drive easily with a standard Phillips-head screwdriver. Our review units each came with six 2TB SATA 3 (6Gbps) hard drives. These drives by default were set up in a RAID 5 configuration to offer 10GB of storage space, leaving 2TB for data redundancy.
RAID 5 is generally the recommended setup for a multiple-bay storage device to offer a balance of capacity, performance, and data integrity. Pegasus R6 also supports RAID 0, 1, 50, 6, 60, and 10. In our trials, the drive switched between RAID 5 and RAID 0 in less than a minute. This is a great bonus as most other RAID-enabled storage devices would take tens of hours to build a RAID 5 array from scratch. Note that if one of the hard drives in the RAID dies, the Pegasus R6 would take up to 9 hours to rebuild the RAID configuration with a replacement drive. The device will still work normally during this time, however, just at a slower speed.
There's nothing to setting up the Pegasus R6. Out of the box, the drive is preformatted in HFS+, and once connected to a computer via Thunderbolt, it's immediately available on your Mac, just like other external storage devices. Despite that easy setup, the drive comes with a well-illustrated Quick Start Guide that walks you through the setup process and explains how its components function.
The drive contains an installer package of the Promise Utility software that enables you to customize the drive by changing its RAID setups, monitoring hard-drive conditions, and so on.
We tested the Pegasus the way we test external storage devices: by copying large amounts of data from one place to another and measuring the device's throughput speed. While this method doesn't show the top theoretical bandwidth of the device, it replicates what you would get from the device in real-world daily usage.
As the R6 is the first Thunderbolt-based storage device, we benchmarked it with two sets of tests. In the first set, we compared its performance with that of internal drives, both traditional hard drives and solid-state drives (SSDs). In the second set, we stacked the Pegasus R6 up against other popular external devices that use USB 3.0, USB 2.0, FireWire, and eSATA connections.