I am so relieved finally to be able to talk about my experience using USB 3.0 on a Mac. It’s a wonderful, seamless experience that is so well-integrated you might not notice it except for the performance. At over 200 MB/s, though, it blows FireWire out of the water and is even faster than nearly any device you’re likely to throw at it.
CalDigit USB 3.0 PCI Express Card Review
No, Apple didn’t send me a sneak peak at some new hardware. My USB 3.0 experience comes courtesy of CalDigit, who sent me their Mac OS X-compatible USB 3.0 PCI Express card for evaluation. I’m pleased as punch with the card and software drivers they delivered, and it makes me crazy that this isn’t included by default in Mac Pro desktops, let alone the new MacBook Pros to be introduced tomorrow.
The CalDigit USB 3.0 adapter is a PCI Express card intended for use in a Mac Pro. A graphic artist friend of mine was kind enough to let me use his very-expensive Apple workstation for testing, and was so impressed that he turned around and ordered a CalDigit card for himself. Installation is a snap – just open the Mac Pro, unscrew the retainer above the PCI Express slots, slide the card in place, and screw everything back together. (Side note: I love Apple’s tower case design!)
I didn’t see a 4-pin mini floppy power connector inside the Mac Pro case, but the CalDigit card does include a compatible header. This would give the ports more power than they can draw from the PCI Express bus itself, but I didn’t see the need. Using only the PCI Express bus, I was able to spin up and use every USB bus-powered drive I tried with no issues.
Installing the software was a snap, too. CalDigit’s driver appears to be locked to only their card (I tried it with a variety of other USB 3.0 cards with no success) but it did support every USB 3.0 drive I tried. This is in stark contrast to the LaCie USB 3.0 driver which only talks to LaCie drives! Specifically, I connected two different Seagate GoFlex USB 3.0 drives, a generic USB 3.0-to-SATA adapter, and Iomega’s screaming-fast USB 3.0 SSD. Every one was instantly available to Mac OS X and visibly out-performed FireWire and USB 2.0.
Real-World Tests
Since this was not my own machine, I was not able to perform my usual benchmarks. But I did test some copy operations, experimenting with USB 2.0 and FireWire 400 and 800 connections. The 1 TB Seagate GoFlex drive pushed over 100 MB/s when using the CalDigit USB 3.0 card, according to my iPhone stopwatch, but were limited to about 45 MB/s and 30 MB/s when using FireWire 400 and USB 2.0, respectively. I had previously tested this drive using eSATA on my iMac and found it topped out at about 110 MB/s, so the drive itself appears to be the bottleneck when using USB 3.0.
Swapping in the Iomega USB 3.0 SSD was eye-opening. This drive proved to be blazing fast in my tests earlier in the week, topping 200 MB/s in both read and write operations when connected to my Asus Cougar Point motherboard running Windows 7. I wasn’t able to perform adequate benchmarks with the Iomega, but my stopwatch showed it accelerating past the GoFlex and easily pushing 150 MB/s or more. I wouldn’t doubt that the CalDigit card is capable of 200 MB/s with an appropriate storage device.
The story was somewhat different under Windows. My instrumented tests (using Atto Disk Benchmark in Windows 7) showed a curious slowdown in write operations compared to the ASMedia USB 3.0 controller selected by Asus for my P8H67-M Pro motherboard. The CalDigit card and drivers matched the ASMedia at over 200 MB/s in read operations to the Iomega SSD, but lagged behind at 150 MB/s when it came to writes. I wonder if perhaps Mac-oriented CalDigit did not optimize their Windows 7 drivers for this card. Of course, 150 MB/s is still more than four times faster than USB 2.0, and I would never have noticed this if I was only using a hard disk drive!
Stephen’s Stance
If you own a Mac Pro, there is no need to wait for Apple to release USB 3.0 hardware and software. I can unreservedly recommend the CalDigit USB 3.0 PCI Express card for Mac Pro owners. The performance and ease of use is well worth the $79 MSRP. With so many external storage vendors rapidly switching to USB 3.0, the days of FireWire 800 being top dog in Mac performance are over. I’d love to connect the new USB 3.0-equipped Drobo S to this card!
CalDigit promised to send me an ExpressCard USB 3.0 adapter to try in my MacBook Pro as soon as they refresh their stock. I’m eager to try it out, since I’ve noted less-thrilling performance in the other USB 3.0 ExpressCard adapters I have tried. Those maxed out at around 110 MB/s in my Dell XPS/Windows 7 laptop, suggesting serious performance limits for the ExpressCard form factor. I am curious to see how the MacBook Pro performs in comparison.