I have been using a matrox TripleHead2Go DP (work) and DualHead2Go DP (home) with a late-2010 Macbook Air (Nvidia GeForce 320M graphics) with two Dell 2007fp monitors at 2*1600x1200@60Hz (i.e., one large display spanning both monitors with MacBook Air closed).
With a mid-2013 Macbook Air the same monitor setup was autodetected as 2*1600x1200@50Hz, which isn't supported by the monitors. Manually switching to 2*1600x1200@60Hz leads to mirroring of the displays in the two extermal montiors at 1600x1200 (macbook closed). Changing to lower resolutions will allow the desktop to span both monitors with the macbook closed but isn't ideal.
I couldn't find anyone else with a similar problem. Matrox customer support blamed the new Intel 5000 GPU in the new Macbook Air and had no further suggestions to fix this issue. Has anyone encountered this problem with the new mid-2013 Macbook Air and the Matrox Dual/TripleHead2Go DP unit(s) and have a work around?
The matrox units have the latest firmware updates, and I'm using the most recent version of the PowerDesk software from matrox.