MacBook – Does the new Air (2012) support Daisy Chaining to two Thunderbolt Displays

Apple maintains a knowledge base article listing which Mac models support either one or two external thunderbolt displays.

• http://support.apple.com/kb/HT4885

The technology does allow for multiple monitors to be daisy chained. In fact, the devices you daisy chain doesn't matter, nor does the order they are in. However, like with the Display Port and eSATA, the problem at the moment is finding actual devices that support this feature. Until Apple or another manufacturer provides monitors with the ports needed for daisy chaining, this will not be possible.

The advantage here is unlike eSATA and Display Port, the bandwidth available will make this more then manageable from the port itself. The biggest obstacle will be the ability to provide enough power to run all these daisy chained devices. Therefore just getting a cable will not be sufficient. Each device will be required to have its own incoming and outgoing port.

Give the technology another year or so it will be more then doable and more mainstream. Apple would most likely also add these ports to their monitors fairly soon, I suspect during the next iMac/Monitor refresh schedule.

The Apple mini-DisplayPort to VGA or HDMI adapter terminates the Thunderbolt chain where it is connected, so until Apple released new MacBook Pro with two Thunderbolt ports (similar to the iMac that has two ports) then you will only get one video signal from the device through the Thunderbolt port.

You may find an inexpensive USB to VGA solution to get around this limitation. Initially they were slower, but the newer ones are getting much faster and the software much better. You can then put the most important content on the Thunderbolt port and have the secondary display served over USB.

Should a Thunderbolt adapter come about that drives two displays, I'll update the answer, but nothing has been released (or even rumored) even though it's clearly something the protocol could support.

I like this knowledge base article for the clear deprecation of which Macs support two Thunderbolt displays and which ones only support one.

• Apple Thunderbolt Display (27-inch): Connection options for Thunderbolt Macs