Apple recently updated their support document for Thunderbolt Macs. According to the document the new MacBook Air 2011 model can connect to a maximum of one Thunderbolt display at a time.
The Apple MacBook Pro, iMac and Mac mini (all mid 2011 model) can support a maximum of two Thunderbolt displays.
The fact that MacBook Air doesn’t support dual monitor output can be frustrating. Needless to say, MacBook Air owners who really want to add two external monitors are left hanging in the air.
But… there’s a solution.
How to Add Two External Monitor To MacBook Air
The first external monitor will be connected through your MBA’s Thunderbolt/Mini DisplayPort port.
You can, however, establish the connection from your MacBook Air to the second monitor through an adapter. A typical USB-to-DVI adapter works well with MacBook Air.
Connect one end of the adapter to the monitor cable, and the other end to the USB port of MacBook Air to bring the second monitor to life.
If you are struggling to find the right adapter, then check out Kensington Universal Multi-Display Adapter available on Amazon for $56. You can buy Kensington adapter from Amazon.
One thing to note that Mac OS X Lion can cause issues when you are adding dual monitor to MacBook Air. However, with the right adapter, and the necessary drivers installed, it is easy to hook up two external monitors without working up a sweat.