On Sat, 21 Jan 2012 13:56:21 -0500, Mathieu Desnoyers mathieu.desnoyers@efficios.com wrote:
Dell U3011 monitor turns to power saving mode when resolution set to 2560 x 1600 (intermittent)
Reproduced with: Linux 2.6.38-1-amd64 (Debian kernel) Linux 3.1.0-1-amd64 (Debian kernel) Linux 3.2.0-1-amd64 (Debian kernel)
The computer is a Lenovo X201 Tablet (Intel QM57 chipset), on a X200 docking station. The docking station uses a DisplayPort cable to connect to the monitor. I tried upgrading my Bios from 1.34/1.13 to 1.38/1.14 (latest), which did not fix the problem. I cannot use anything else than DisplayPort in this case to connect the monitor at 2560 x 1600, because this resolution requires either the bandwidth provided by a dual-link DVI (which I cannot connect in my docking station), or DisplayPort.
I use this same monitor, and have run it with an X200 in the past.
Can you capture a dmesg output with the kernel parameter drm.debug=0xe set? That will let us see the DP link training adventure and see what's broken. If you can, separate traces of working and non-working tries would be nice.
And, of course, trying 3.3-rc1 would be helpful as that's what any test patches would be developed on top of.