VGA/DVI cables are not long for this world


A few weeks back, soon after the release of their beta Mac drivers, the kind folk at DisplayLink mailed me one of their USB adapters, pretty much out of the blue (I have corresponded with them in the past, but the opportunity to tinker with their solution at leisure was a great surprise). I got a DVI one with a very spiffy cable:

Being temporarily bereft of a desk at home1 I was unable to try it out properly there, but on a whim I set it up in a VM inside Fusion without any Mac drivers (thanks to Fusion’s great USB support), causing XP to believe it had an extra monitor:

This was mostly because I wanted to see how Fusion handled USB devices that are unsupported by the host (since I often have to test USB devices on Windows), but also because I had been musing about the feasibility of having an XP VM act as a “secondary computer” of sorts (yes, I keep thinking about thin clients of all kinds).

At work, however, I was able to hook up the adapter to the MacBook Pro I have at hand and get it working without any hassles over lunchtime – my desk layout these days is a pain and I had to rig it via one of the USB extension cords we ship with USB modems, but I was able to run two external displays without any hassles whatsoever – one via the built-in DVI port and another via the DisplayLink DVI.

Sorry, no (public) pictures – I’ve got a whole bunch of sensitive stuff on my desk these days…

Performance was good enough for a bunch of terminal windows and web pages, although I did come across a few screen redraw issues exactly as outlined in the release notes.

Having no graphics acceleration means, of course, that the user experience is far from ideal, but the important thing is that it worked as advertised – it was just another display, and popped up in all the right places as such (i.e., in System Preferences, menu bar, etc.).

Connecting it to my XP laptop (a Dell D410) yielded a very responsive display, indistinguishable from the usual performance I get from the Intel GMA 950’s external VGA port (and actually a little better, since the component sourcing guys at Dell must be cheapskates and its video out is somewhat noisy).

And this is where the potential sinks in: Since I loathe docking stations, I use a USB KVM to hook up an external keyboard and mouse to my laptop – which means that I have to plug in the power, video and USB plugs every time I arrive at my desk, but which I vastly prefer to XP’s fundamentally broken “Undock Computer” option. So if I was using a USB hub instead of the KVM, I could simply plug the dongle there and cut that to two cables – power and everything else.

But back to performance, and back to the Mac: The bottom line is that for a beta of something that they managed to do without significant support from Apple, the beta DisplayLink driver is very impressive.

The overall experience was not unlike using an older Mac (like my iBook G3), and I see no reason why Apple shouldn’t give them a hand developing this further – or even adopting their tech and pumping it up a notch2.

I await further driver developments with interest – in the meantime, all I have to do is persuade my wife to let me buy a couple of 24” displays…

1 A more accurate statement would be that I am bereft of both a desk and a home, since the damn renovation isn’t finished yet. But I digress.

2 Can you say ’30” Studio Displays with Wireless USB?’ That kind of connectivity would fit the MacBook Air like a glove. And “it works today”:http://www.everythingusb.com/displaylink.html.”