Multi-monitor setup Mac laptop

joezorry's pick

Only the 15" and 17" Macbook Pros can drive two Apple Thunderbolt displays. support.apple.com/kb/HT4885

There are solutions for USB-based video; and there is a Matrox solution that I would research very carefully before trying: www.matrox.com/graphics/en/products/gxm/

If you are wondering about the Thunderbolt PCIe breakout boxes that were announced last year, there appears to be no solution for graphics cards coming anytime soon: www.magma.com/thunderbolt.asp

For those that don't want to follow that link, here is the key quote:

"There is an interoperability issue with MacOS using graphics (GPU) cards externally through Thunderbolt. Unfortunately, external graphics solutions for MacOS X do not work and we do not expect a resolution from Apple in the short term. We realize that external graphics support is a feature that many users want so we’ll let you know if this changes. For the time being our recommendation may be to run Windows using Boot Camp, but this is not yet confirmed as a working solution."

Given Apple's growing disinterest in professional users, I wouldn't hold my breath that Magma or any third-party hardware developer is going to get much help from Apple for such a niche use case.

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joezorry 2012-02-05 01:35:04

Thanks for the input and the links.
Matrox might be a solution, but I need to do more research, as you said.
If there was a thunderbolt adapter that would expand to a USB3 hub and a regular DVI/Displayport then the Displaylink solution might be better, but maybe the Thunderbolt bandwidth just is not enough to handle that.

MtnSloth 2012-02-05 20:07:22

It is not a question of bandwidth. The problem is the lack of GPU support for devices that present as a PCIe device on a Thunderbolt chain instead of as a display device.

It is reasonable to assume that one could get around these display limitations with USB display devices. USB 2.0 is no problem (although USB 2.0 displays are relatively low resolution). The problems with USB 3.0 are two-fold:

OS X does not natively support USB 3.0. LaCie wrote their own driver for their USB 3.0 peripheral cards (for the Mac Pro and ExpressCard/34 equippped MacBook Pros), and other vendors may have done the same,
While I am sure I read of a Thunderbolt hub that includes a USB 3.0 port, I can't find a link to a shipping product (or even one with an announced ship date). Hopefully, someone else can provide a link.

If I am reading Apple's docs correctly, the ideal Mac for your use case might be the Mac Mini with AMD graphics as it can support two Thunderbolt displays as well as an HDMI display. That would give you two very expensive displays and one that should be relatively inexpensive. I would get confirmation from Apple just in case there is an undocumented gotcha.

joezorry 2012-02-08 09:11:03

Actually thought about that solution, It would be a crazy setup with a Mac Mini and then two Apple displays and one with HDMI-out.
But if I understand your reply correctly is that the Thunderbolt port on the Air don't have the GPU strength to carry two external displays on the same connection?

MtnSloth 2012-02-09 00:09:56

That is my understanding as well.

gdgt

Multi-monitor setup Mac laptop

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