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New 27-inch iMac Supports Dual External Display Output

One of the most exciting things about today’s new iMacs (s aapl) (and the thing that will probably result in me buying one) are the dual Thunderbolt ports on the 27-inch iMac. They’re great in that they provide a lot of potential I/O transfer power, but more importantly because it allows the new iMac to output to two external monitors simultaneously, Apple confirmed to me this morning.

Users who want to use more than one external monitor with their Mac have so far been fairly limited in their options. You can use a USB-to-DVI or VGA solution, as I’ve mentioned before, or you can use a wireless solution such as Air Display, but both solutions offer downsides (USB video adapters don’t support things like 3D acceleration and wireless solutions inevitably have some degree of lag) that native wired DisplayPort output does not.

Now, using two Mini DisplayPort adapters plugged in to the 27-inch iMacs Thunderbolt ports, users can simultaneously output to two monitors in addition to the main built-in screen of the iMac. It won’t necessarily clog up your Thunderbolt ports, either, since the tech supports daisy-chaining. That means you should be able to connect to Thunderbolt-compatible storage and then on to a display after that, too, without any loss of quality.

Having the ability to output to two additional monitors built-in makes the 27-inch iMac a very attractive machine for audio/visual professionals, and also for pretty much anyone who values more screen real estate in their work. Before today, you could spend hundreds of dollars trying to add-on the ability to your Mac using third-party software and hardware. This could very well be the tipping point for many who were considering an upgrade, but were unsure about whether or not they really needed to do so.

Mini DisplayPort input (which allowed the previous generation 27-inch iMac to act as an external monitor itself) appears to be missing from the list of features on the new iMac, but as far as I’m concerned it’s a very small price to pay for the huge added benefit of being able to output to more than one additional monitor. This has the power to significantly change people’s workflows and adds considerable creative benefit to a machine that’s already favored by creative professionals. Plus, once the Thunderbolt accessory market matures, having two of the ports will really help the new iMac anchor a considerably more capable work (and play) station.

9 Responses to “New 27-inch iMac Supports Dual External Display Output”

  1. CharonPDX

    DisplayPort has always been (theoretically) capable of daisy-chaining multiple displays. And Apple advertised Thunderbolt from day one as being able to support two DisplayPort displays simultaneously on one Thunderbolt port. (It will require either a chaining through a device that has multiple ‘expansion’ Thunderbolt ports, or using a DisplayPort display with a daisy-chain port; both of which do not yet exist.)

    I would expect that we’ll see updated Cinema Displays with ‘true’ Thunderbolt ports in them, and with two such ports, so that the display can act as the ‘hub’ for further Thunderbolt devices.

    So, based on Apple’s prior statement, it may be possible to have up to FOUR external displays on the latest 27″ iMac. (The latest Radeon chips do support three displays out of the box, and there are models available that support six displays on a single GPU…)

  2. I bought my iMac in November ’10 and one of the major selling points to me was the DisplayPort input so I could still have my PC and use the iMacs screen as a monitor. If it’s gone I won’t be able to upgrade in the future.

  3. The new iMacs look nice! I love that there are two ThunderBolt ports. Hopefully, more external drive companies will support it so I can back up all my video fast. I think I’m going to wait until they start shipping with Mac OSX Lion so I don’t have to pay a huge upgrade fee.