I've got the same problem (slightly different board: GA-Z87N-WIFI, but with 2x HDMI, 1x DVI). The symptoms seem to be the same, though I'm running a slightly different kernel (3.10.7).
I'm running Arch, not Ubuntu, and I'm also happy to play around with possible fixes, including patching compiling new kernels as necessary.
I've got the same problem (slightly different board: GA-Z87N-WIFI, but with 2x HDMI, 1x DVI). The symptoms seem to be the same, though I'm running a slightly different kernel (3.10.7).
I'm running Arch, not Ubuntu, and I'm also happy to play around with possible fixes, including patching compiling new kernels as necessary.