W520 Tri-head Display Setup, Nvidia Driver Power 2 External Monitors

1. Originally want to setup a xorg.conf file using

2. Then found this using Bumblebee etc,

3. Then noticed the post with more reference.

Finally got it to work, not like 2's approach with Intel driver control 2 monitors (can not make it work), I must use Nvidia driver to control 2 external monitors.

After patched xserver-xorg-video-intel, xrandr lists LVDS1, VGA1 and VIRTUAL, but VGA1 is always disconnected no matter how I change /etc/X11/xorg.conf.

I can get 1 external monitor (which is always the one connected to VGA port) to work by as in http://sagark.org/optimal-ubuntu-graphics-setup-for-thinkpads/

Noticed BOTH external moniters wake up (indicator light from yellow to blue) to grey (black) screen, this seems they are controlled by Nvidia driver.

Reading  https://github.com/Bumblebee-Project/Bumblebee/wiki/FAQ, using

optirun nvidia-settings -c :8

indeed verify Nvidia displays 2 external monitors, and I can set twinview etc.

Why only one external monitor show stuff, and the other is grey?

Rescue comes just from xrandr, the key is to assign a larger resolution to VIRTUAL, and twinview within those 2 external monitors works:

$ cvt 3840 1080 60
# 3840x1080 59.96 Hz (CVT) hsync: 67.16 kHz; pclk: 346.00 MHz
Modeline "3840x1080_60.00"  346.00  3840 4088 4496 5152  1080 1083 1093 1120 -hsync +vsync

$ xrandr --newmode "3840x1080"  346.00  3840 4088 4496 5152  1080 1083 1093 1120 -hsync +vsync
$ xrandr --addmode VIRTUAL 3840x1080

1 comment:

Daniel S. Haischt said...

You would achieve the same if you would use thinkdisp accompanied by an /etc/thinkdisp/config.ini that contains the custom 3840x1200 resolution.