The display is capable of 2560x1600 @ 60Hz, which is detected from the EDID
response. When changing to this resolution (e.g. on X server startup), the
desktop will display briefly (0.5-2 seconds) at the correct resolution, and
then the display (Dell U3014) reports "no signal" and goes in to power save
mode.
I suspected a hardware issue, but the 2560x1600 resolution works fine on this
hardware with:
- The console
- The Jessie Beta 1 graphical installer
- The Ubuntu 14.04.1 installer
- Ubuntu 14.04.1 itself