UGA-125 compatible with Apple Cinema displays?


#1

Is the UGA-125 compatible with Apple’s 20" cinema displays? I’ve tried unsuccessfully to connect each of my two 20" displays to my MacBook with no luck. I’ve tried the 1.5 driver as well as the 1.6 beta. The display connected to the adapter is not recognized, and all I get on the screen is vertical banding/lines and ghost images on the right side of the display. Help!


#2

Hi Rose,

Thanks for posting! I’m sorry, I suspect I won’t have good news for you. But we’ll get you fixed up either way.

Let’s confirm a few things:

* The Cinema display uses Apple’s unique ADP (Apple Display Connector), and you’re connecting to the USB to DVI adapter via an Apple DVI to ADC Display Adapter. Is that correct?
* There are at least two versions of the 20" Cinema display (http://support.apple.com/kb/sp52)). Can you tell - do you have the M8893ZM/A model with 1680 by 1050 pixels native resolution?

In general, the Apple Cinema displays have been problematic because they behave differently than other monitors. The two main differences are:

  1. Most monitors are able to handle their native mode and any lower mode via a hardware scaler. Cinema displays have reduced cost by not including a hardware scaler – they work in their native mode and rely on software scaling for most lower modes. But software scaling over USB isn’t feasible performance-wise, and isn’t supported by the DisplayLink drivers today.
  2. The ADC connector and adapter appear to sometimes cause irregularities in the EDID (monitor capabilities) information returned over DVI (e.g. see http://displaylink.org/forum/showthre… )

If yours is one of the 1680x1050 Cinema displays, then unfortunately you’ll need a USB adapter that’s able to exactly set that mode. The UGA-125 (with its DL-125 chip inside) can only make it up to 1440x900, so that explains the basic problem you’re having now. You’ll need to upgrade to an adapter with either the DL-165 or DL-195 chip – they will get to the native mode you need on the 20".

We never want customers stuck with hardware that doesn’t work on their setup, so we have 30 day no-hassle returns through Amazon. So for returing your UGA-125, just visit http://www.amazon.com/gp/css/returns/…

And while we can’t really recommend it because of the different characteristics of the Cinema displays, if you then decide to purchase one of the higher resolution adapters (so it can set 1680x1050 native), it appears that some users have things working fine with Cinema displays – but keep in mind that there are occasional reports of the extra hops from ADC->DVI->USB opening the doors to other problems.

Sorry there isn’t an easier answer for Apple’s Cinema displays. Hope this information helps. Please let us know if you have any other questions.

Best wishes and thank you!
Bernie


#3