My environment is Fedora 20 x86_64 running on a Lenovo W530 with nVidia K1000M graphics.
My usual setup has an IBM T221 monitor (“Big Bertha”, which can run at 3840x2400) connected via a short mini-display-port-to-DVI cable. I run the external monitor at 1920x1200 resolution.
I have usually installed kmod-nvidia-x.x.x from the rpmfusion repository, and updated kmod-nvidia at the same time as updating the kernel. (I only found out about the akmod-nvidia option recently.) But the problem described below is the same if I install kmod-nvidia, akmod-nvidia, or download the NVIDIA-Linux-xxxx.run installation script.
This configuration all worked well until “recently”, with the T221 correctly detected, and X running perfectly at 1920x1200. But possibly since a recent upgrade or two (I have been living with the problem for a few weeks) the external monitor is not detected correctly. It is detected as present, but X attempts to run at 5760x1080 (where the native W530 resolution is 1920x1080). As 1920x1080 is not a resolution supported by the T221, I get nothing on the monitor. When I run nvidia-setings, the screen layout seems to be “1920x1080 (the laptop screen), a 1920x1080 blank, and another 1920x1080 screen (the monitor)”
The standard nouveau driver correctly displays on the external monitor, so it is not a connectivity issue.
I haven’t had the chance to roll back kernel and driver levels to see if I can find out when the rot set in.
Is it possible that a recent change to the driver has caused this issue?
I should stress that I am not an expert in X and drivers, so please use short words!
Thanks in advance – Peter M