A Thunderbolt to eSATA adaptor is the
solution. LaCie’s eSATA Hub looks like the Little Big Disk drives, but its
purpose is to connect other eSATA drives to your Thunderbolt Mac. On the back
are two Thunderbolt ports, a connector for an external power supply, and two
eSATA ports.
Hub’s been good to me. Thunderbolt hubs from LaCie and Sonnet (top) connect
eSATA drives; Seagate’s Thunderbolt adaptor (right) connects the company’s
GoFlex range of drives
These work at SATA-II speeds, which caps
their maximum bandwidth at 3Gbit/ sec. Still, that enables transfer rates far
in excess of what any hard drive can sustain, meaning the interface is no
longer a bottleneck. By way of example, Western Digital’s high-performance
Caviar Black drives are quoted as achieving 138MB per second, or 1.1Gbit/sec,
even in their SATA-III versions (SATA-III allows up to 6Gbit/sec).
We tested the LaCie eSATA Hub with one of
LaCie’s existing multi-interface d2 drives. When connected to a Mac’s FireWire
800 port, it achieved an average write speed of 74MB per second and a maximum
write speed of 75.2MB per second in our large file test. The steady performance
was an indication that it was being held back by FireWire. Switching to its
eSATA interface using the hub, these figures rose to 131.1MB and 183MB per
second. Same drive, twice the speed.
We
tested the LaCie eSATA Hub with one of LaCie’s existing multi-interface d2
drives. When connected to a Mac’s FireWire 800 port, it achieved an average
write speed of 74MB per second and a maximum write speed of 75.2MB per second
in our large file test
Seagate’s GoFlex range is purposely designed
so that the port used to connect to a computer is replaceable. You might use
USB with one computer, but swap it for FireWire with another. GoFlex
Thunderbolt adaptors are available through Apple’s online store; a single-port
version for portable drives means you don’t need to carry a power adaptor,
while the desktop version has a second Thunderbolt port for pass-through.
We tested the portable version of
Seagate’s Thunderbolt adaptor. With our FreeAgent GoFlex drive connected over
FireWire 800, the average write speed was 63.8MB per second, and the maximum
was 64MB. Using the Thunderbolt port, these increased to 87.4MB and 224.4MB per
second, but that maximum was an extraneous result; the next nearest speed
recorded was 124.7MB per second, and performance trailed off with larger test
files, hitting a low of 66.3MB per second. So there’s less of a consistent gain
to be had than with desktop drives, which tend to offer faster sustained
performance.
Seagate’s
Thunderbolt adaptor
The connector that attaches Seagate’s
adaptors to a GoFlex drive is a standard SATA port. So in theory you could
attach a bare SSD to one of its Thunderbolt adaptors to add super-fast storage
to your Mac. However, bear in mind that OS X Lion doesn’t support TRIM on
non-Apple SSDs. TRIM is a technology that optimises an SSD’s speed on the fly;
without it, the drive’s speed will be reduced over time, a bit like the way
hard disks used to need defragmenting. The only way to regain full speed is to
fully erase the drive, which in turn means backing up and restoring all your
data - hardly convenient. So a new standalone Thunderbolt SSD, such as those
tested here, makes more sense.
“There are plenty of external drives with
eSATA ports, but Macs don’t have them. A Thunderbolt to eSATA adaptor is the
solution”
