Matrox DualHead2go adapter broadens your monitor horizons
If your widescreen ambitions can't be contained by a mere 1920x1080 HD screenscape, the fine folks at Matrox have a solution for you. The DualHead2Go Digital Mac Edition display adapter, priced around US$160, is built and marketed specifically for the Thunderbolt and DisplayPort-enabled Mac models.
It pairs up with Matrox's PowerDesk software to enable spanned displays, rather than defining each external monitor as its own real estate. If you have the required two matching-resolution monitors, you can achieve some truly breathtaking resolutions.
Design
Like the rest of Matrox's line, the DualHead's pro-style design would be perfectly at home in a video editing workstation or studio. The unit, about the size of a pack of cards, sports two DVI-D ports on the back to connect your two displays for pairing. The aluminum case features cheesegrater-style ventilation holes that match nicely with the look of the aging Mac Pro desktop.
I hooked up the DualHead to a Retina MacBook Pro via the provided mini DisplayPort to full-size DisplayPort adapter. This larger connector may be unfamiliar to most Mac users, but it's frequently seen on recent-model Windows laptops; it looks like a slightly cockeyed HDMI plug. The other necessary connection on the front of the unit is USB, which provides power for the adapter.
Considering the number of cables going into and out of this small device, a bit of onboard cable management wouldn't be amiss. You could velcro or cable-tie your cables to the DualHead, since it doesn't get particularly hot during usage.
Users who need even more space to spread out have the option of stepping up to the TripleHead2go unit, which teams three monitors instead of two -- for about 2x the price.
Performance
Unlike the dual-DVI connection that enables full resolution on Apple's 30" Cinema Display, the DualHead creates a virtual spanned display across both of the connected external monitors. In my testing, with two smaller Cinema Displays, the combined resolution got up to the supported maximum of 3840x1200 -- more than enough real estate for almost anyone.
Given that this "one big monitor" is actually two displays with a hefty border in between, window management becomes more important than in a simplex setup. Matrox's PowerDesk software lets you define target cells for your apps, quickly moving windows around the screen and swapping content from your LCD to the wide external duplex display. It took me a few passes through the documentation to get a handle on the best way to manage the display cells; Matrox's instructions and the utility interface are aimed more at a video professional audience than at consumers.
The responsiveness of the big screen was surprisingly good. Matrox's hardware doesn't do any hefty graphics processing of its own; rather, it presents the large virtual display resolution to the onboard GPU and lets the graphics chip in the Mac do the heavy lifting of drawing on that big canvas. On the Retina MBP, I didn't notice any dragging or slow performance onscreen, even with several QuickTime movies playing at once. Older Mac hardware might not fare quite as well -- Matrox's compatibility guide for adapters is a good place to start if you're considering options.
Wrap-up
With its base requirement of two resolution-matched external displays plus a solid GPU-equipped Mac, the DualHead2go is fairly described as a specialty item. If your needs demand extreme widescreen, however, and you'd rather repurpose older DVI monitors than shell out $999 for a 27" Thunderbolt display, Matrox is there to help you out.
Pros
Unique widescreen capability
Small and unobtrusive
Impressive performance
Cons
Software is a bit confusing
Requires identical resolution monitors
Limited consumer appeal
Who is it for?
Graphics and video pros who believe wider is better.
